Wow! The same thing happen to me a few years back. Sold 2 Orion 275G4 amps through paypal and as soon as I notified the buyer that the items shipped, contact was suddenly losed and a claim was filed. I provided paypal with the proper info (tracking #, etc) but they required electronic signature for items over $250 eventhough I had them insured. So they charged my account the amount for the amps and I had topay=up or have collection jack my credit up. I filed a claim with the post office but since it was actually delivered, they wouldn't pay. Long story short, make sure you request an electronic signature when selling items or you will get scammed...