used part purchase: fraud

The owner of this company sold us a part using the US Mail service. He insisted that we mail him a check in advance instead of the standard procedure of paying with a credit card. It appears this was done in order to prevent us from challenging the transaction in the future. The part that was supplied was fairly expensive, $500.00 and after installation was determined to be a faulty part. Attempting to resolve this issue was impossible with this company. They finally asked us to ship the faulty part back for their "inspection". after many weeks of trying to get them to verify the part as defective we finally just bought a brand new part from the local Porsche dealer, installed it on our customers car and finished the repair. After at least 30 or 40 phone calls, etc, we came to the conclusion that the entire process from start to finish was just a scam. A way of cheating an out of state repair shop out of $500.00 by knowingly shipping a junk part, getting paid up front for it by a check and than asking from the "scam" part to be sent back so they can do it again to another unsuspecting company. To date we have not received any sort of refund, we have no replacement part from this company and we are out the $500.00 we spent. Its very sad this is allowed to happen but we are currently investing if we can file a claim with the United States Attorneys office for Mail Fraud.