I made a ton selling coins on eBay, and got the money for them as well.
What I did was say "NO REFUNDS WHATSOEVER" in the description and in the Paypal info, and said the user needed to put their wallet address in the paypal comments. I also stated that there would be no refunds in any case, and there will be video proof of the transaction taking place, to prove the coins were sent to the address in the paypal checkout. I sold like thousands of dollars worth of coins, listed at $20-25+ each (back in july 2011) and scammers would buy them up like $500 at a time.
The scammers would do a reversal on the transaction in a systematic fashion, and since I used Freez Screen Video Capture to make videos of myself transferring the coins to the person's wallet that they entered in the paypal reciept (which was open and evident in the video), it served as solid proof. Paypal returned 100% of the money to me, with the exception of one small transaction where the person did a reversal on their credit card.. Paypal couldn't help that.
When you do a transaction dispute, and they look at the video, there is no denying it.
I paid for ALL my mining equipment with the coins that I sold to would-be scammers on eBay last summer!
eBay has since changed its policies quite a bit, I don't think it's safe to sell coins there anymore unless they were casascius, a "bitcoin cheque", or a private key on a piece of paper that you can physically mail to them and get a tracking number, since that is allowed.
I'm sure you believe this and perhaps you've had really good luck but I think it's important to people who are new to selling coins on eBay to know that this entire post is utter bullshit.
Unless you have a tracking number from the shipping forms used on PayPal you're fucked. And then you still might be fucked. I've been selling on eBay for well over a year now. My mistakes and the mistakes made by others have shown me that you need to ship a physical product, you need to use the paypal shipping interface, and you need to be very very very very wary...
If you come to a ebay/paypal dispute with a screenshot or a video, they're going to laugh at you.
Ship paper coins, or metal coins. You'll still get scammed but less often.