standard ERPNext currently supports below 2 sales return processes
- return against delivery note
- return from sales invoice with both Is Return and Update Stock checked
from business process side, sales return is normally initiated / requested by sales person, just like delivery note and sales invoice, there should be Is Return check box in sales order also. this is how other ERP like SAP handles sales return process.
per my study, the following simple changes can make return from sales order possible
add two fields Is Return and Return Against to sales order doctype
allow copy for Is Return field in Delivery Note doctype
add extra condition to make sure only when return_against exists triggers the update of previous doc status, in order to support return delivery against return sales order, other than return against delivery note as of now.
update sales_invoice.py submit and cancel method to allow update return sales order billing status when return sales invoice linked with return sales order
do you support making the above change to the core?