Product Exchange at Store Level

Hello,

How will we process a product exchange at store level? To be more prescise, lets assume we are delivering product to a store from a self service truck, we take in a case of widgets and the customer returns 2 widgets ea. He wants an even exchange of the product and not to go through the process of creating an rma, getting a credit and then getting a debit for the exchange. Is there a simple way of tackling this?

Thanks in advance for any ideas.

Regards,

Francisco Elguera