Be able to "return" rentals from within the app

Now the customer has a separate receipt type "Driving plates" in which the type and number reported returned is entered. Having the employee fill in an end date to a rental item was too difficult, partly because often only a portion is returned. Now in the office they manually look for the rental item with the receipt, if not all was returned they adjust the number and duplicate the rental, and mark the road plate receipt as "Linked to rental".

Nicest is something like a slider with "(Part) returned" and then indicate how much (and for ride plates clean/dirty return). If part is returned automatically duplicate the sale and rental and for that part that is returned mark it as checked oid.