Similar thing happened to me. Selling some reproduction parts I make for old cars. Guy wants 10, says he's on a freighter and needs them right away, sends overnight check for $1200, about 5 times the parts worth. Says keep all but a hundred for him, I say sure. If the check clears I'll send the parts. Well take the check to the bank it's drawn on, no account exists. No really? I send him an email telling him to f-off and don't waste my time. Tried to give all of the info to the bank and the cops, neither are interested in pursuing it.