N K,
You need to create one dummy material and run the process with stock .
I don't agree with your suggestion!
In order to create a return order, you want the user to create the entire Sales cycle and then do the return.
Why should the user create a billing document (for the normal sales cycle) when a billing document is already created in the legacy system?
What and how to address the postings with the creation of the Accounting document?
Further you are talking about dummy material? Manipulating the stock!
Suppose there are 100 return orders to be created, would you suggest to created 400 addition documents? (PO, SO, delivery, invoice)??
Again I donot agree with your suggestion of creating PO is the system (using ME21N)!
Do you create a PO in the normal OTC cycle?
It is only SO>Delivery>Billing (not PO)