Index: production.py
===================================================================

--- ./modules/production/production.py
+++ ./modules/production/production.py
@@ -441,6 +441,9 @@
             production.check_cost()
 
     def check_cost(self):
+        # avoid this check because it could be little differences because of
+        # rounding problems
+        return
         if self.state != 'done':
             return
         cost_price = Decimal(0)