diff --git a/src/blenderbim/blenderbim/bim/module/cost/operator.py b/src/blenderbim/blenderbim/bim/module/cost/operator.py
index 4b3c39ea4b..be1475ac60 100644
--- a/src/blenderbim/blenderbim/bim/module/cost/operator.py
+++ b/src/blenderbim/blenderbim/bim/module/cost/operator.py
@@ -332,6 +332,7 @@ class EnableEditingCostItemValues(bpy.types.Operator):
         props = context.scene.BIMCostProperties
         props.active_cost_item_id = self.cost_item
         props.cost_item_editing_type = "VALUES"
+        bpy.ops.bim.disable_editing_cost_item_value()
         return {"FINISHED"}
 
 
diff --git a/src/ifcopenshell-python/ifcopenshell/api/cost/remove_cost_item.py b/src/ifcopenshell-python/ifcopenshell/api/cost/remove_cost_item.py
index 003cf31931..c9dc7a3cf9 100644
--- a/src/ifcopenshell-python/ifcopenshell/api/cost/remove_cost_item.py
+++ b/src/ifcopenshell-python/ifcopenshell/api/cost/remove_cost_item.py
@@ -1,3 +1,6 @@
+import ifcopenshell.api
+
+
 class Usecase:
     def __init__(self, file, **settings):
         self.file = file
@@ -7,4 +10,13 @@ class Usecase:
 
     def execute(self):
         # TODO: do a deep purge
+        for inverse in self.file.get_inverse(self.settings["cost_item"]):
+            if inverse.is_a("IfcRelNests"):
+                if inverse.RelatingObject == self.settings["cost_item"]:
+                    for related_object in inverse.RelatedObjects:
+                        ifcopenshell.api.run("cost.remove_cost_item", self.file, cost_item=related_object)
+                elif inverse.RelatedObjects == tuple(self.settings["cost_item"]):
+                    self.file.remove(inverse)
+            elif inverse.is_a("IfcRelAssignsToControl"):
+                self.file.remove(inverse)
         self.file.remove(self.settings["cost_item"])
diff --git a/src/ifcopenshell-python/ifcopenshell/api/sequence/remove_task.py b/src/ifcopenshell-python/ifcopenshell/api/sequence/remove_task.py
index 2366678dda..f468a28a6a 100644
--- a/src/ifcopenshell-python/ifcopenshell/api/sequence/remove_task.py
+++ b/src/ifcopenshell-python/ifcopenshell/api/sequence/remove_task.py
@@ -25,4 +25,6 @@ class Usecase:
                         ifcopenshell.api.run("sequence.remove_task", self.file, task=related_object)
                 elif inverse.RelatedObjects == tuple(self.settings["task"]):
                     self.file.remove(inverse)
+            elif inverse.is_a("IfcRelAssignsToControl"):
+                self.file.remove(inverse)
         self.file.remove(self.settings["task"])