diff --git a/pyproject.toml b/pyproject.toml
index 1535a28ad..1ce3d8ab7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -44,7 +44,6 @@ init_typed = true
 warn_required_dynamic_aliases = true
 warn_untyped_fields = true
 
-
 [tool.ruff]
 # see: https://beta.ruff.rs/docs/rules/
 ignore = [
diff --git a/vizro-core/docs/pages/tutorials/explore_components.md b/vizro-core/docs/pages/tutorials/explore_components.md
index 6d750ae65..091f3277d 100644
--- a/vizro-core/docs/pages/tutorials/explore_components.md
+++ b/vizro-core/docs/pages/tutorials/explore_components.md
@@ -710,7 +710,7 @@ and how to bring them together.
 For future dashboard creations, you can explore more about the available dashboard `components` by going through the
 [user guide](../user_guides/components.md). To gain more in-depth knowledge about the usage and configuration
 details of `controls`, check out the user guides dedicated to [Filters](../user_guides/filters.md), [Parameters](../user_guides/parameters.md)
-and [Selectors](../user_guides/selectors.md). If you'd like to understand more about different ways to configure the navigation of your dashboard, head 
+and [Selectors](../user_guides/selectors.md). If you'd like to understand more about different ways to configure the navigation of your dashboard, head
 to [Navigation](../user_guides/navigation.md).
 
 Vizro doesn't end here, and we only covered the key features, but there is still much more to explore! You can learn:
diff --git a/vizro-core/docs/pages/user_guides/components.md b/vizro-core/docs/pages/user_guides/components.md
index 2446fa3cb..7aea43d8a 100755
--- a/vizro-core/docs/pages/user_guides/components.md
+++ b/vizro-core/docs/pages/user_guides/components.md
@@ -402,8 +402,8 @@ and provide an attribute selector to select images with that matching URL hash.
 
 !!! note
 
-    This section describes how to use the [`Card`][vizro.models.Card] component to create a navigation 
-    card. To configure the navigation panel on the left hand side of the screen, refer to the 
+    This section describes how to use the [`Card`][vizro.models.Card] component to create a navigation
+    card. To configure the navigation panel on the left hand side of the screen, refer to the
     [guide on navigation](navigation.md).
 
 
diff --git a/vizro-core/docs/pages/user_guides/navigation.md b/vizro-core/docs/pages/user_guides/navigation.md
index 4771415ef..fd9a00166 100644
--- a/vizro-core/docs/pages/user_guides/navigation.md
+++ b/vizro-core/docs/pages/user_guides/navigation.md
@@ -2,7 +2,7 @@
 
 This guide shows you how to use and customize the navigation that appears on the left of your dashboard.
 
-The [`Dashboard`][vizro.models.Dashboard] model accepts a `navigation` argument, where you can enter a [`Navigation`][vizro.models.Navigation] model. This enables you to group pages together and customise how they appear in your navigation.
+The [`Dashboard`][vizro.models.Dashboard] model accepts a `navigation` argument, where you can enter a [`Navigation`][vizro.models.Navigation] model. This enables you to group pages together and customize how they appear in your navigation.
 
 ## Using the default navigation
 
@@ -14,9 +14,9 @@ By default, if the `navigation` argument is not specified, Vizro creates a navig
         from vizro import Vizro
         import vizro.plotly.express as px
         import vizro.models as vm
-        
+
         iris = px.data.iris()
-        
+
         page_1 = vm.Page(
             title="My first page",
             components=[
@@ -35,7 +35,7 @@ By default, if the `navigation` argument is not specified, Vizro creates a navig
                 vm.Graph(figure=px.scatter(iris, x="sepal_length", y="sepal_width", color="species")),
             ],
         )
-        
+
         dashboard = vm.Dashboard(pages=[page_1, page_2, page_3])
         Vizro().build(dashboard).run()
         ```
@@ -143,7 +143,7 @@ Another way to group together pages in the navigation is to use a [`NavBar`][viz
 !!! example "Using `NavBar`"
     === "app.py"
         ```py
-         # page_1, page_2, page_3 defined as in default example        
+         # page_1, page_2, page_3 defined as in default example
         dashboard = vm.Dashboard(
             pages=[page_1, page_2, page_3],
             navigation=vm.Navigation(
@@ -178,7 +178,7 @@ Here, the first level of the navigation hierarchy ("Group A" and "Group B") is r
 
 ## Customizing the navigation bar
 
-Under the hood, [`NavBar`][vizro.models.NavBar] uses [`NavLink`][vizro.models.NavLink] to build the icons in the navigation bar. It is possible to customise the navigation further by providing the `NavLink`s yourself.
+Under the hood, [`NavBar`][vizro.models.NavBar] uses [`NavLink`][vizro.models.NavLink] to build the icons in the navigation bar. It is possible to customize the navigation further by providing the `NavLink`s yourself.
 
 ### `NavLink` examples
 
@@ -187,7 +187,7 @@ The same configuration for [grouping pages](#grouping-your-pages) applies inside
 !!! example "Accordions inside a `Navlink`"
     === "app.py"
         ```py
-         # page_1, page_2, page_3 defined as in default example        
+         # page_1, page_2, page_3 defined as in default example
         dashboard = vm.Dashboard(
             pages=[page_1, page_2, page_3],
             navigation=vm.Navigation(
@@ -213,7 +213,7 @@ The same configuration for [grouping pages](#grouping-your-pages) applies inside
           nav_selector:
             type: nav_bar
             items:
-              - label: Section 1 
+              - label: Section 1
                 pages:
                   Group A:
                     - My first page
@@ -231,7 +231,7 @@ You can alter the icons used by specifying the name of the icon in the [Google M
 !!! example "Custom icon"
     === "app.py"
         ```py
-         # page_1, page_2, page_3 defined as in default example        
+         # page_1, page_2, page_3 defined as in default example
         dashboard = vm.Dashboard(
             pages=[page_1, page_2, page_3],
             navigation=vm.Navigation(
@@ -258,12 +258,12 @@ You can alter the icons used by specifying the name of the icon in the [Google M
           nav_selector:
             type: nav_bar
             items:
-              - label: Section 1 
+              - label: Section 1
                 icon: bar_chart
                 pages:
                   - My first page
                   - My second page
-              - label: Section 1 
+              - label: Section 1
                 icon: pie_chart
                 pages:
                   - My third page
@@ -271,4 +271,4 @@ You can alter the icons used by specifying the name of the icon in the [Google M
     === "Result"
         [![CustomIcons]][CustomIcons]
 
-    [CustomIcons]: ../../assets/user_guides/navigation/custom_icons.png
\ No newline at end of file
+    [CustomIcons]: ../../assets/user_guides/navigation/custom_icons.png
diff --git a/vizro-core/examples/from_yaml/dashboard.yaml b/vizro-core/examples/from_yaml/dashboard.yaml
index 6e01fa8ca..b081f14ea 100644
--- a/vizro-core/examples/from_yaml/dashboard.yaml
+++ b/vizro-core/examples/from_yaml/dashboard.yaml
@@ -11,8 +11,8 @@ pages:
         type: graph
     title: My first page
   - components:
-     - text: My text here
-       type: card
+      - text: My text here
+        type: card
     title: My second page
   - components:
       - figure:
@@ -36,4 +36,3 @@ navigation:
         icon: pie_chart
         pages:
           - My third page
-
diff --git a/vizro-core/hatch.toml b/vizro-core/hatch.toml
index 866284d47..707b62da8 100644
--- a/vizro-core/hatch.toml
+++ b/vizro-core/hatch.toml
@@ -64,7 +64,7 @@ test-integration = [
   "- pytest tests/integration/test_examples.py::test_json_dashboard --headless",
   "- pytest tests/integration/test_examples.py::test_yaml_dashboard --headless",
   "pytest tests/integration/test_navigation.py"
-  ]
+]
 test-js = "./tools/run_jest.sh {args}"
 test-unit = "pytest tests/unit {args}"
 update-snyk-requirements = "python ../tools/generate_snyk_requirements.py {args}"
diff --git a/vizro-core/pyproject.toml b/vizro-core/pyproject.toml
index c323749bc..b65a2586f 100644
--- a/vizro-core/pyproject.toml
+++ b/vizro-core/pyproject.toml
@@ -66,7 +66,6 @@ branch = true
 parallel = true
 source_pkgs = ["vizro"]
 
-
 [tool.pytest.ini_options]
 addopts = [
   # Allow test files to have the same name in different directories.
diff --git a/vizro-core/src/vizro/models/_dashboard.py b/vizro-core/src/vizro/models/_dashboard.py
index d4c9d12fd..7619dfafa 100644
--- a/vizro-core/src/vizro/models/_dashboard.py
+++ b/vizro-core/src/vizro/models/_dashboard.py
@@ -15,12 +15,10 @@
 from vizro.actions._action_loop._action_loop import ActionLoop
 from vizro.models import Navigation, VizroBaseModel
 from vizro.models._models_utils import _log_call
-
 from vizro.models._navigation._navigation_utils import _NavBuildType
 
 if TYPE_CHECKING:
     from vizro.models import Page
-
     from vizro.models._page import _PageBuildType
 
 logger = logging.getLogger(__name__)
diff --git a/vizro-core/src/vizro/models/_navigation/_navigation_utils.py b/vizro-core/src/vizro/models/_navigation/_navigation_utils.py
index 1d89eb50e..7bac806cd 100644
--- a/vizro-core/src/vizro/models/_navigation/_navigation_utils.py
+++ b/vizro-core/src/vizro/models/_navigation/_navigation_utils.py
@@ -29,7 +29,7 @@ def _validate_pages(pages):
 # This is just used for type checking. Ideally it would inherit from some dash.development.base_component.Component
 # (e.g. html.Div) as well as TypedDict, but that's not possible, and Dash does not have typing support anyway. When
 # this type is used, the object is actually still a dash.development.base_component.Component, but this makes it easier
-# to see what contract the component fulfils by making the expected keys explicit.
+# to see what contract the component fulfills by making the expected keys explicit.
 class _NavBuildType(TypedDict):
     nav_bar_outer: html.Div
     nav_panel_outer: html.Div
diff --git a/vizro-core/src/vizro/models/_navigation/nav_bar.py b/vizro-core/src/vizro/models/_navigation/nav_bar.py
index 32485578c..cdbc93427 100644
--- a/vizro-core/src/vizro/models/_navigation/nav_bar.py
+++ b/vizro-core/src/vizro/models/_navigation/nav_bar.py
@@ -8,7 +8,7 @@
 
 from vizro.models import VizroBaseModel
 from vizro.models._models_utils import _log_call
-from vizro.models._navigation._navigation_utils import _validate_pages, _NavBuildType
+from vizro.models._navigation._navigation_utils import _NavBuildType, _validate_pages
 from vizro.models._navigation.nav_link import NavLink
 
 
diff --git a/vizro-core/src/vizro/models/_navigation/navigation.py b/vizro-core/src/vizro/models/_navigation/navigation.py
index 6b6f13102..d9ad6d22f 100644
--- a/vizro-core/src/vizro/models/_navigation/navigation.py
+++ b/vizro-core/src/vizro/models/_navigation/navigation.py
@@ -5,7 +5,7 @@
 
 from vizro.models import VizroBaseModel
 from vizro.models._models_utils import _log_call
-from vizro.models._navigation._navigation_utils import _validate_pages, _NavBuildType
+from vizro.models._navigation._navigation_utils import _NavBuildType, _validate_pages
 from vizro.models._navigation.accordion import Accordion
 from vizro.models.types import NavPagesType, NavSelectorType
 
diff --git a/vizro-core/src/vizro/models/_page.py b/vizro-core/src/vizro/models/_page.py
index da84cf9da..06f36ddbd 100644
--- a/vizro-core/src/vizro/models/_page.py
+++ b/vizro-core/src/vizro/models/_page.py
@@ -18,7 +18,7 @@
 # This is just used for type checking. Ideally it would inherit from some dash.development.base_component.Component
 # (e.g. html.Div) as well as TypedDict, but that's not possible, and Dash does not have typing support anyway. When
 # this type is used, the object is actually still a dash.development.base_component.Component, but this makes it easier
-# to see what contract the component fulfils by making the expected keys explicit.
+# to see what contract the component fulfills by making the expected keys explicit.
 class _PageBuildType(TypedDict):
     control_panel_outer: html.Div
     component_container_outer: html.Div
diff --git a/vizro-core/tests/conftest.py b/vizro-core/tests/conftest.py
index 7aaf6d0ab..3b71a917f 100644
--- a/vizro-core/tests/conftest.py
+++ b/vizro-core/tests/conftest.py
@@ -2,7 +2,6 @@
 
 from vizro import Vizro
 
-
 # Allow our custom assert functions in tests_utils/asserts.py to do introspection nicely still.
 # See https://pytest.org/en/7.4.x/how-to/assert.html#assertion-introspection-details
 pytest.register_assert_rewrite("asserts")
@@ -16,10 +15,3 @@ def reset_managers():
     Vizro._reset()
     yield
     Vizro._reset()
-
-
-# AM: simplify this and dashboard fixtures
-@pytest.fixture()
-def vizro_app():
-    """Fixture to instantiate Vizro/Dash app. Required when needing to register pages."""
-    yield Vizro()
diff --git a/vizro-core/tests/integration/test_navigation.py b/vizro-core/tests/integration/test_navigation.py
index 771a02eaa..1910fd6e2 100644
--- a/vizro-core/tests/integration/test_navigation.py
+++ b/vizro-core/tests/integration/test_navigation.py
@@ -1,8 +1,7 @@
 import pytest
+from asserts import assert_component_equal
 
 import vizro.models as vm
-
-from asserts import assert_component_equal
 from vizro import Vizro
 from vizro.managers import model_manager
 
diff --git a/vizro-core/tests/tests_utils/asserts.py b/vizro-core/tests/tests_utils/asserts.py
index 5445dd733..1a32c93dd 100644
--- a/vizro-core/tests/tests_utils/asserts.py
+++ b/vizro-core/tests/tests_utils/asserts.py
@@ -9,7 +9,6 @@ def strip_keys(object, keys):
 
     This makes it easy to compare dictionaries generated from Dash components we've created that contain random IDs.
     """
-
     if isinstance(object, dict):
         object = {key: strip_keys(value, keys) for key, value in object.items() if key not in keys}
     elif isinstance(object, list):
diff --git a/vizro-core/tests/unit/vizro/actions/_action_loop/test_get_action_loop_components.py b/vizro-core/tests/unit/vizro/actions/_action_loop/test_get_action_loop_components.py
index d7698380f..9db0d3e4b 100644
--- a/vizro-core/tests/unit/vizro/actions/_action_loop/test_get_action_loop_components.py
+++ b/vizro-core/tests/unit/vizro/actions/_action_loop/test_get_action_loop_components.py
@@ -68,7 +68,7 @@ def trigger_to_actions_chain_mapper_component(request):
 
 
 @pytest.fixture
-def managers_one_page_two_components_two_controls(dash_data_table_with_id):
+def managers_one_page_two_components_two_controls(vizro_app, dash_data_table_with_id):
     """Instantiates managers with one page that contains two controls and two components."""
     vm.Dashboard(
         pages=[
@@ -116,7 +116,7 @@ def managers_one_page_two_components_two_controls(dash_data_table_with_id):
 
 
 @pytest.fixture
-def managers_one_page_no_actions():
+def managers_one_page_no_actions(vizro_app):
     """Instantiates managers with one "empty" page."""
     vm.Dashboard(
         pages=[
@@ -134,7 +134,7 @@ def managers_one_page_no_actions():
 class TestGetActionLoopComponents:
     """Tests getting required components for the action loop."""
 
-    @pytest.mark.usefixtures("vizro_app", "managers_one_page_no_actions")
+    @pytest.mark.usefixtures("managers_one_page_no_actions")
     def test_no_components(self):
         result = _get_action_loop_components()
         result = json.loads(json.dumps(result, cls=plotly.utils.PlotlyJSONEncoder))
@@ -143,7 +143,7 @@ def test_no_components(self):
 
         assert result == expected
 
-    @pytest.mark.usefixtures("vizro_app", "managers_one_page_two_components_two_controls")
+    @pytest.mark.usefixtures("managers_one_page_two_components_two_controls")
     @pytest.mark.parametrize(
         "gateway_components, "
         "action_trigger_components, "
diff --git a/vizro-core/tests/unit/vizro/conftest.py b/vizro-core/tests/unit/vizro/conftest.py
index 92e7bb625..4d6914e6b 100644
--- a/vizro-core/tests/unit/vizro/conftest.py
+++ b/vizro-core/tests/unit/vizro/conftest.py
@@ -5,6 +5,7 @@
 
 import vizro.models as vm
 import vizro.plotly.express as px
+from vizro import Vizro
 from vizro.tables import dash_data_table
 
 
@@ -42,16 +43,28 @@ def standard_go_chart(gapminder):
 
 
 @pytest.fixture()
-def page1():
-    return vm.Page(title="Page 1", components=[vm.Button(), vm.Button()])
+def page_1():
+    return vm.Page(title="Page 1", components=[vm.Button()])
 
 
 @pytest.fixture()
-def page2():
-    return vm.Page(title="Page 2", components=[vm.Button(), vm.Button()])
+def page_2():
+    return vm.Page(title="Page 2", components=[vm.Button()])
 
 
 @pytest.fixture()
-def dashboard(page1, page2):
-    dashboard = vm.Dashboard(pages=[page1, page2])
+def vizro_app():
+    """Fixture to instantiate Vizro/Dash app.
+
+    Required if Vizro._pre_build or dashboard.pre_build is called since dash.register_page can only be called after
+    app instantiation.pages.
+    """
+    return Vizro()
+
+
+@pytest.fixture()
+def prebuilt_two_page_dashboard(vizro_app, page_1, page_2):
+    """Minimal two page dashboard, used mainly for testing navigation."""
+    dashboard = vm.Dashboard(pages=[page_1, page_2])
+    dashboard.pre_build()
     return dashboard
diff --git a/vizro-core/tests/unit/vizro/models/_navigation/conftest.py b/vizro-core/tests/unit/vizro/models/_navigation/conftest.py
index 6f010a015..200ada86e 100644
--- a/vizro-core/tests/unit/vizro/models/_navigation/conftest.py
+++ b/vizro-core/tests/unit/vizro/models/_navigation/conftest.py
@@ -3,11 +3,6 @@
 import pytest
 
 
-@pytest.fixture()
-def prebuilt_dashboard(dashboard):
-    dashboard.pre_build()
-
-
 @pytest.fixture()
 def pages_as_list():
     return ["Page 1", "Page 2"]
diff --git a/vizro-core/tests/unit/vizro/models/_navigation/test_accordion.py b/vizro-core/tests/unit/vizro/models/_navigation/test_accordion.py
index 739660285..894275c73 100644
--- a/vizro-core/tests/unit/vizro/models/_navigation/test_accordion.py
+++ b/vizro-core/tests/unit/vizro/models/_navigation/test_accordion.py
@@ -1,19 +1,18 @@
 """Unit tests for vizro.models.Accordion."""
-import json
 import re
 
 import dash_bootstrap_components as dbc
 import pytest
+from asserts import assert_component_equal
 from dash import html
 from pydantic import ValidationError
 
 import vizro.models as vm
-from asserts import assert_component_equal
-
 from vizro._constants import ACCORDION_DEFAULT_TITLE
 
+pytestmark = pytest.mark.usefixtures("prebuilt_two_page_dashboard")
+
 
-@pytest.mark.usefixtures("vizro_app", "prebuilt_dashboard")
 class TestAccordionInstantiation:
     """Tests accordion model instantiation."""
 
@@ -49,7 +48,6 @@ def test_invalid_page(self, pages):
             vm.Accordion(pages=pages)
 
 
-@pytest.mark.usefixtures("vizro_app", "prebuilt_dashboard")
 class TestAccordionBuild:
     """Tests accordion build method."""
 
diff --git a/vizro-core/tests/unit/vizro/models/_navigation/test_nav_bar.py b/vizro-core/tests/unit/vizro/models/_navigation/test_nav_bar.py
index 0a629534b..d8b40515c 100644
--- a/vizro-core/tests/unit/vizro/models/_navigation/test_nav_bar.py
+++ b/vizro-core/tests/unit/vizro/models/_navigation/test_nav_bar.py
@@ -1,17 +1,17 @@
 """Unit tests for vizro.models.NavBar."""
 import re
 
+import dash_bootstrap_components as dbc
 import pytest
+from asserts import assert_component_equal
 from dash import html
 from pydantic import ValidationError
 
 import vizro.models as vm
-import dash_bootstrap_components as dbc
 
-from asserts import assert_component_equal
+pytestmark = pytest.mark.usefixtures("prebuilt_two_page_dashboard")
 
 
-@pytest.mark.usefixtures("vizro_app", "prebuilt_dashboard")
 class TestNavBarInstantiation:
     """Tests NavBar model instantiation."""
 
@@ -51,7 +51,6 @@ def test_invalid_page(self, pages):
             vm.NavBar(pages=pages)
 
 
-@pytest.mark.usefixtures("vizro_app", "prebuilt_dashboard")
 class TestNavBarPreBuildMethod:
     def test_default_items(self, pages_as_dict):
         nav_bar = vm.NavBar(pages=pages_as_dict)
@@ -71,7 +70,6 @@ def test_items_with_with_pages_icons(self, pages_as_dict):
         assert nav_bar.items[1].icon == "filter_2"
 
 
-@pytest.mark.usefixtures("vizro_app", "prebuilt_dashboard")
 class TestNavBarBuildMethod:
     """Tests NavBar model build method."""
 
@@ -112,7 +110,7 @@ def test_nav_bar_not_active_pages_as_dict(self, pages_as_dict):
             built_nav_bar["nav_panel_outer"], html.Div(hidden=True, id="nav_panel_outer"), keys_to_strip={}
         )
 
-    def test_nav_bar_active_pages_as_list(self, pages_as_list):
+    def test_nav_bar_not_active_pages_as_list(self, pages_as_list):
         nav_bar = vm.NavBar(pages=pages_as_list)
         nav_bar.pre_build()
         built_nav_bar = nav_bar.build(active_page_id="Page 3")
diff --git a/vizro-core/tests/unit/vizro/models/_navigation/test_nav_item.py b/vizro-core/tests/unit/vizro/models/_navigation/test_nav_item.py
index 010e79377..6e54e3bc9 100644
--- a/vizro-core/tests/unit/vizro/models/_navigation/test_nav_item.py
+++ b/vizro-core/tests/unit/vizro/models/_navigation/test_nav_item.py
@@ -3,14 +3,15 @@
 
 import dash_bootstrap_components as dbc
 import pytest
+from asserts import assert_component_equal
 from dash import html
 from pydantic import ValidationError
 
 import vizro.models as vm
-from asserts import assert_component_equal
+
+pytestmark = pytest.mark.usefixtures("prebuilt_two_page_dashboard")
 
 
-@pytest.mark.usefixtures("vizro_app", "prebuilt_dashboard")
 class TestNavLinkInstantiation:
     """Tests NavLink model instantiation."""
 
@@ -55,7 +56,6 @@ def test_invalid_page(self, pages):
             vm.NavLink(pages=pages)
 
 
-@pytest.mark.usefixtures("vizro_app", "prebuilt_dashboard")
 class TestNavLinkPreBuildMethod:
     def test_nav_link(self, pages_as_dict):
         nav_link = vm.NavLink(label="Label", pages=pages_as_dict)
@@ -64,7 +64,6 @@ def test_nav_link(self, pages_as_dict):
         assert nav_link._nav_selector.pages == pages_as_dict
 
 
-@pytest.mark.usefixtures("vizro_app", "prebuilt_dashboard")
 @pytest.mark.parametrize("pages", ["pages_as_dict", "pages_as_list"])
 class TestNavLinkBuildMethod:
     """Tests NavLink model build method."""
diff --git a/vizro-core/tests/unit/vizro/models/_navigation/test_navigation.py b/vizro-core/tests/unit/vizro/models/_navigation/test_navigation.py
index 86577ec11..73abd6fdc 100644
--- a/vizro-core/tests/unit/vizro/models/_navigation/test_navigation.py
+++ b/vizro-core/tests/unit/vizro/models/_navigation/test_navigation.py
@@ -1,17 +1,17 @@
 """Unit tests for vizro.models.Navigation."""
 import re
 
+import dash_bootstrap_components as dbc
 import pytest
+from asserts import assert_component_equal
 from dash import html
 from pydantic import ValidationError
 
 import vizro.models as vm
-from asserts import assert_component_equal
 
-import dash_bootstrap_components as dbc
+pytestmark = pytest.mark.usefixtures("prebuilt_two_page_dashboard")
 
 
-@pytest.mark.usefixtures("vizro_app", "prebuilt_dashboard")
 class TestNavigationInstantiation:
     def test_navigation_mandatory_only(self):
         navigation = vm.Navigation()
@@ -45,7 +45,6 @@ def test_invalid_page(self, pages):
             vm.Navigation(pages=pages)
 
 
-@pytest.mark.usefixtures("vizro_app", "prebuilt_dashboard")
 class TestNavigationPreBuildMethod:
     def test_default_nav_selector(self, pages_as_dict):
         navigation = vm.Navigation(pages=pages_as_dict)
@@ -72,7 +71,6 @@ def test_non_default_nav_selector_with_pages(self, pages_as_dict):
         assert navigation.nav_selector.pages == {"Group": ["Page 1"]}
 
 
-@pytest.mark.usefixtures("vizro_app", "prebuilt_dashboard")
 class TestNavigationBuildMethod:
     """Tests navigation model build method."""
 
diff --git a/vizro-core/tests/unit/vizro/models/test_dashboard.py b/vizro-core/tests/unit/vizro/models/test_dashboard.py
index 59320b2f6..1977b6419 100644
--- a/vizro-core/tests/unit/vizro/models/test_dashboard.py
+++ b/vizro-core/tests/unit/vizro/models/test_dashboard.py
@@ -29,7 +29,7 @@ def dashboard_container():
 
 
 @pytest.fixture()
-def mock_page_registry(dashboard, page1, page2):
+def mock_page_registry(prebuilt_two_page_dashboard, page_1, page_2):
     return OrderedDict(
         {
             "Page 1": {
@@ -44,12 +44,12 @@ def mock_page_registry(dashboard, page1, page2):
                 "description": "",
                 "order": 0,
                 "supplied_order": 0,
-                "supplied_layout": partial(dashboard._make_page_layout, page1),
+                "supplied_layout": partial(prebuilt_two_page_dashboard._make_page_layout, page_1),
                 "supplied_image": None,
                 "image": None,
                 "image_url": None,
                 "redirect_from": None,
-                "layout": partial(dashboard._make_page_layout, page1),
+                "layout": partial(prebuilt_two_page_dashboard._make_page_layout, page_1),
                 "relative_path": "/",
             },
             "Page 2": {
@@ -64,12 +64,12 @@ def mock_page_registry(dashboard, page1, page2):
                 "description": "",
                 "order": 1,
                 "supplied_order": 1,
-                "supplied_layout": partial(dashboard._make_page_layout, page2),
+                "supplied_layout": partial(prebuilt_two_page_dashboard._make_page_layout, page_2),
                 "supplied_image": None,
                 "image": None,
                 "image_url": None,
                 "redirect_from": None,
-                "layout": partial(dashboard._make_page_layout, page2),
+                "layout": partial(prebuilt_two_page_dashboard._make_page_layout, page_2),
                 "relative_path": "/page-2",
             },
             "not_found_404": {
@@ -84,12 +84,12 @@ def mock_page_registry(dashboard, page1, page2):
                 "description": "",
                 "order": None,
                 "supplied_order": None,
-                "supplied_layout": dashboard._make_page_404_layout(),
+                "supplied_layout": prebuilt_two_page_dashboard._make_page_404_layout(),
                 "supplied_image": None,
                 "image": None,
                 "image_url": None,
                 "redirect_from": None,
-                "layout": dashboard._make_page_404_layout(),
+                "layout": prebuilt_two_page_dashboard._make_page_404_layout(),
                 "relative_path": "/not-found-404",
             },
         }
@@ -99,30 +99,30 @@ def mock_page_registry(dashboard, page1, page2):
 class TestDashboardInstantiation:
     """Tests model instantiation and the validators run at that time."""
 
-    def test_create_dashboard_mandatory_only(self, page1, page2):
-        dashboard = vm.Dashboard(pages=[page1, page2])
+    def test_create_dashboard_mandatory_only(self, page_1, page_2):
+        dashboard = vm.Dashboard(pages=[page_1, page_2])
         assert hasattr(dashboard, "id")
-        assert dashboard.pages == [page1, page2]
+        assert dashboard.pages == [page_1, page_2]
         assert dashboard.theme == "vizro_dark"
         assert dashboard.title is None
         assert isinstance(dashboard.navigation, vm.Navigation)
         assert dashboard.navigation.pages == ["Page 1", "Page 2"]
 
-    def test_create_dashboard_mandatory_and_optional(self, page1, page2):
-        dashboard = vm.Dashboard(pages=[page1, page2], theme="vizro_light", title="Vizro")
+    def test_create_dashboard_mandatory_and_optional(self, page_1, page_2):
+        dashboard = vm.Dashboard(pages=[page_1, page_2], theme="vizro_light", title="Vizro")
         assert hasattr(dashboard, "id")
-        assert dashboard.pages == [page1, page2]
+        assert dashboard.pages == [page_1, page_2]
         assert dashboard.theme == "vizro_light"
         assert dashboard.title == "Vizro"
         assert isinstance(dashboard.navigation, vm.Navigation)
         assert dashboard.navigation.pages == ["Page 1", "Page 2"]
 
-    def test_navigation_pages_automatically_populated(self, page1, page2):
-        dashboard = vm.Dashboard(pages=[page1, page2])
+    def test_navigation_pages_automatically_populated(self, page_1, page_2):
+        dashboard = vm.Dashboard(pages=[page_1, page_2])
         assert dashboard.navigation.pages == ["Page 1", "Page 2"]
 
-    def test_navigation_with_pages(self, page1, page2):
-        dashboard = vm.Dashboard(pages=[page1, page2], navigation=vm.Navigation(pages=["Page 1"]))
+    def test_navigation_with_pages(self, page_1, page_2):
+        dashboard = vm.Dashboard(pages=[page_1, page_2], navigation=vm.Navigation(pages=["Page 1"]))
         assert dashboard.navigation.pages == ["Page 1"]
 
     def test_mandatory_pages_missing(self):
@@ -137,25 +137,23 @@ def test_field_invalid_pages_input_type(self):
         with pytest.raises(ValidationError, match="4 validation errors for Dashboard"):
             vm.Dashboard(pages=[vm.Button()])
 
-    def test_field_invalid_theme_input_type(self, page1):
+    def test_field_invalid_theme_input_type(self, page_1):
         with pytest.raises(ValidationError, match="unexpected value; permitted: 'vizro_dark', 'vizro_light'"):
-            vm.Dashboard(pages=[page1], theme="not_existing")
+            vm.Dashboard(pages=[page_1], theme="not_existing")
 
 
 class TestDashboardPreBuild:
     """Tests dashboard pre_build method."""
 
-    @pytest.mark.usefixtures("vizro_app")
-    def test_dashboard_page_registry(self, dashboard, mock_page_registry):
-        dashboard.pre_build()
+    def test_dashboard_page_registry(self, prebuilt_two_page_dashboard, mock_page_registry):
         result = dash.page_registry
         expected = mock_page_registry
         # Str conversion required as comparison of OrderedDict values result in False otherwise
         assert str(result.items()) == str(expected.items())
 
-    def test_create_layout_page_404(self, dashboard, mocker):
+    def test_create_layout_page_404(self, prebuilt_two_page_dashboard, mocker):
         mocker.patch("vizro.models._dashboard.get_relative_path")
-        result = dashboard._make_page_404_layout()
+        result = prebuilt_two_page_dashboard._make_page_404_layout()
         result_image = result.children[0]
         result_div = result.children[1]
 
@@ -164,12 +162,10 @@ def test_create_layout_page_404(self, dashboard, mocker):
         assert isinstance(result_div, html.Div)
 
 
-@pytest.mark.usefixtures("vizro_app")
 class TestDashboardBuild:
     """Tests dashboard build method."""
 
-    def test_dashboard_build(self, dashboard_container, dashboard):
-        dashboard.pre_build()
-        result = json.loads(json.dumps(dashboard.build(), cls=plotly.utils.PlotlyJSONEncoder))
+    def test_dashboard_build(self, dashboard_container, prebuilt_two_page_dashboard):
+        result = json.loads(json.dumps(prebuilt_two_page_dashboard.build(), cls=plotly.utils.PlotlyJSONEncoder))
         expected = json.loads(json.dumps(dashboard_container, cls=plotly.utils.PlotlyJSONEncoder))
         assert result == expected
diff --git a/vizro-core/tests/unit/vizro/models/test_types.py b/vizro-core/tests/unit/vizro/models/test_types.py
index 0d7042ec7..910c30b7b 100644
--- a/vizro-core/tests/unit/vizro/models/test_types.py
+++ b/vizro-core/tests/unit/vizro/models/test_types.py
@@ -1,5 +1,4 @@
 import importlib
-from pathlib import Path
 
 import plotly.express as plotly_express
 import plotly.graph_objects as go