diff --git a/src/ifcopenshell-python/ifcopenshell/api/cost/calculate_cost_item_resource_value.py b/src/ifcopenshell-python/ifcopenshell/api/cost/calculate_cost_item_resource_value.py
index bace1c6d12..4b85ee8e44 100644
--- a/src/ifcopenshell-python/ifcopenshell/api/cost/calculate_cost_item_resource_value.py
+++ b/src/ifcopenshell-python/ifcopenshell/api/cost/calculate_cost_item_resource_value.py
@@ -108,7 +108,7 @@ class Usecase:
         for resource in resources:
             cost, unit = ifcopenshell.util.resource.get_cost(resource)
             if not cost:
-                cost = ifcopenshell.util.resource.get_parent_cost(resource) # Concept to standardise - Not defined in schema, but this makes manual scheduling of resources 10x faster and less duplicate data.
+                cost, unit  = ifcopenshell.util.resource.get_parent_cost(resource) # Concept to standardise - Not defined in schema, but this makes manual scheduling of resources 10x faster and less duplicate data.
             quantity = ifcopenshell.util.resource.get_quantity(resource)
             if not cost or not quantity:
                 continue
@@ -117,4 +117,4 @@ class Usecase:
             total_cost += cost * quantity
         if total_cost:
             cost_value = ifcopenshell.api.run("cost.add_cost_value", self.file, parent=self.settings["cost_item"])
-            cost_value.AppliedValue = self.file.createIfcMonetaryMeasure(total_cost)
+            cost_value.AppliedValue = self.file.createIfcMonetaryMeasure(total_cost)
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