First off, you never refund any buyer for things they dont return. They will purposely create a false complaint to see what they can get way with and if they can get the item for free. What the buyer did was feedback extortion and you fell for it. First and formost, you dont know this person or anyone you do business with online from a hole in the wall, they dont care about you nor should you care about them, they are out to rip you off, not everyone but a certain percentage. You have to conduct yourself the same way for everyone, with the first thing that comes first is you. Establish policies, if your out anything you dont want to be out more. NEVER refund anyone, or send another product to the person unless you get the other one back, and make them pay for the return. If they are going to return something, your going to loose the transaction, so why pay for their postage!