diff --git a/src/bonsai/bonsai/bim/module/spatial/prop.py b/src/bonsai/bonsai/bim/module/spatial/prop.py
index 27e36e518e..20a1cc1d18 100644
--- a/src/bonsai/bonsai/bim/module/spatial/prop.py
+++ b/src/bonsai/bonsai/bim/module/spatial/prop.py
@@ -65,22 +65,22 @@ def update_name(self: "BIMContainer", context: bpy.types.Context) -> None:
         tool.Ifc.get_object(tool.Ifc.get().by_id(ifc_definition_id)).name = self.name
 
 
-def update_active_container_index(self, context):
+def update_active_container_index(self: "BIMSpatialDecompositionProperties", context: bpy.types.Context) -> None:
     SpatialDecompositionData.data["subelement_class"] = SpatialDecompositionData.subelement_class()
     if tool.Blender.get_enum_safe(self, "subelement_class") is None:
         self.subelement_class = SpatialDecompositionData.data["subelement_class"][0][0]
     tool.Spatial.load_contained_elements()
 
 
-def update_should_include_children(self, context):
+def update_should_include_children(self: "BIMSpatialDecompositionProperties", context: bpy.types.Context) -> None:
     tool.Spatial.load_contained_elements()
 
 
-def update_element_mode(self, context):
+def update_element_mode(self: "BIMSpatialDecompositionProperties", context: bpy.types.Context) -> None:
     tool.Spatial.load_contained_elements()
 
 
-def update_container_obj(self, context):
+def update_container_obj(self: "BIMObjectSpatialProperties", context: bpy.types.Context) -> None:
     if self.container_obj is None or not (obj := context.active_object):
         return
     if not (element := tool.Ifc.get_entity(self.container_obj)):
diff --git a/src/ifcopenshell-python/ifcopenshell/api/project/append_asset.py b/src/ifcopenshell-python/ifcopenshell/api/project/append_asset.py
index 0f5fc0ec8d..2af75e2f3e 100644
--- a/src/ifcopenshell-python/ifcopenshell/api/project/append_asset.py
+++ b/src/ifcopenshell-python/ifcopenshell/api/project/append_asset.py
@@ -169,7 +169,7 @@ class Usecase:
             self.target_class = "IfcPresentationStyle"
             return self.append_presentation_style()
 
-    def get_existing_element(self, element):
+    def get_existing_element(self, element: ifcopenshell.entity_instance) -> Union[ifcopenshell.entity_instance, None]:
         if element.id() in self.added_elements:
             return self.added_elements[element.id()]
         try:
@@ -180,7 +180,7 @@ class Usecase:
             elif element.is_a("IfcProfileDef"):
                 return [e for e in self.file.by_type("IfcProfileDef") if e.ProfileName == element.ProfileName][0]
         except:
-            return False
+            return None
 
     def append_material(self):
         self.whitelisted_inverse_attributes = {