Dangers of buying PDAs from eBay

It can seem like a great temptation to buy a PDA off eBay, but let me tell you that it can be a headache. I bought one, the fellow vanished and I was forced to file an item not received claim. Thankfully I got my money back via PayPal (they ROCK!!!!!). Did I learn my lesson? Nope, I went and bought another one from a fellow with almost 200 feedback and good feedback score. He advertised a "Like New" PDA - I got it and it won't sync to my computer no matter what I have done or tried (checked for SUDS) and it has breaks in it that he did not mention in ad and is trying to blame on me or the USPS, and two taped places on the cord he had not mentioned that he did admit he knew about.

I'm very frustrated and annoyed, but mostly because he is holding my feedback hostage. If he actually made an effort I would give good or at least neutral feedback, but the guy is talking himself into negative feedback and I have never gave anyone a negative before.