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This really sounds like an awful transaction I had over 10 years ago, I ended up calling the police in the seller's hometown, the detective I talked to was great and eventually got the seller to return my money. I'm not sure how willing some police departments would be to chase down small claims like this these days, so try the mail fraud route first. Be sure to save all your communications with the seller, and keep track of all communication with whatever agency you work with to get this resolved.