What do I do about this?

[conklinauto]

I sold an item AFTER the buyer approached me and asked if I had one.  We talked about it for a couple of weeks via ebay messages and I sent them pics.  I finally put up a BiN for them with the description "Nice used condition"  That was the entire description.  NOW, two weeks later, they want to return it because it's "not as described".  Well it came out of the vehiucle I was driving (until it was stolen and wrecked).  I know the condition AND they had it described in detail in messages as well as pics prior to the auction.

More interesting, after the purchase they had me ship it to their son in another states, so the person who paid, who is now wanting to return it, has never even seen it.  They tried to pressure me into letting them return it on their dime immediately while the case is open...I don't see me doing that...

So am I stuck taking back a perfectly good item that didn't even HAVE any specific auction description?  There's certainly something very, very wrong with the entire situation...