What would you do ?

[MichiganMan24]

So annoying. Total jerk behavior. At the end of the day probably not much you can do, but as someone who's sold cards in the past, there's nothing more frustrating than dealing with a customer who wastes your time. Best of luck dealing with it.

[Exhibitman]

Buyer's a liar: unless you are forced to refund (like via eBay) hang tough and tell him to go **** himself. I'd also go to your local post office and start an investigation. They may have images of the package and his signature.