Situation:
- Customers get annual invoices, there is no quotation or order left 
- Invoice was written in 2017 
- Some Prices have been changed in the meantime. 
- New invoice can be written now. 
- To save time, we want to duplicate the old invoice. But the new invoice gets the old prices again. 
Is there any possibility to create a new invoice with the duplicate function with new prices?





 
                        
you can override copy() function
Thanks
Can you tell me where to find it? I also had this idea, but I have searched for hours, and didn't find it yet.