It's a good policy to try to keep your cool in any eBay related dispute. The key word is to settle things AMICABLY. Sometimes it is neither the buyer nor the seller's fault...I recently had a transaction that went like this...Sold a stack of catalogues to a buyer. Buyer did not choose to purchase insurance. I shipped a large box full of my items to the buyer. Buyer received my box but all the items were replaced with multiple issues of one sports magazine. Buyer contacts me, all riled up, stating to the effect "I want the items I paid for or a refund." I actually did keep my cool at this point, not knowing what had happened. I asked for and received photos of the box and contents. I was able to then verify that (1) it was my box and (2) not my contents. By looking at the photos, I saw that the box had been shrinkwrapped, which I do not do. I asked further questions such as was the box sitting on his doorstep, did he pick it up at the P.O. etc. He said it was handed to him by his mail carrier. I knew I had hand delivered it to my local P.O. So....somewhere between the post offices, something happened.
Buyer is still steamed, thinking I have played fast and loose. I am unsure whether he is scamming me. I am unwilling to give a refund because I know I mailed correct items out. He files a Paypal dispute which I think is a little early yet since we are still delving into the mystery. Neither of us can figure out why if someone stole the items, they would take the trouble to replace them with other stuff. I ask that a postal complaint be made but buyer is not confident of a resolution that way. I go to file it myself even though he has the evidence and the claims guy says that it could have been tampered with by accident at a bulk mail center. Box could have split open and they filled it with what they thought belonged. If so, there is a chance items will be recovered since I had a list.
This only happened within the last 30 days so items are still in the netherworld. By the way, Paypal ruled in my favor.
The point is, keep calm. Don't jump to conclusions until all the facts are in. In this strange transaction, neither buyer nor seller were at fault.