I sell Pokemon booster boxes, and Amazon ships them in a bubble envelope. On top of that customer open the boxes and return them opened about 3 times a month. I have a solution to put every booster box in a brown cardboard box, then print something out with a seal that says do not open is seal is broken. As well write once seal is broken cannot be returned. Would that be against TOS to write that? I know Amazon would allow the return, it is just so scammers think twice before opening it.
If the customer want’s to return an item within 30 days for any reason you need to accept the request.
Also, not returnable does not mean not refundable.
If you don;t want it back you can refund without dealing with a return.
How would this stop a scammer?
How are they scamming you?
They open the box - touch the item, don;t like it and want to return it…sounds like a normal buyer.
You posted under FBA so I assume you are using that. Amazon will issue a full refund. If you want to be able to deduct 50% and the cost of the return label, you need to use FBM.
Somethings do not work with FBA. Or they do if you can still make profit with the scammers taken into account.