Well, I buy and sell A LOT on ebay. And my general principles in doing so are simply this:

When selling, I bend over backwards to list every flaw in any item I sell, and I take the position that the customer is always right, and I never argue with any customer who asks for a refund, and I issue it promptly. Net result, I've never gotten a negative in many hundreds of sales, and fewer than 1% of my buyers have ever asked to return an item for a refund. Oh, and BTW, if I actually inadvertently did misrepresent an item, I refund shipping both ways as well - even though my sales terms state that return shipping is the customer's responsibility. It's happened to me exactly 3 times in over 700 sales, that I shipped an item that had a defect I was unaware of and hence did not fully disclose.

When buying - I always expect that the item is not quite as good as described - but that the price I paid is enough of a bargain to more than cover that difference, such that if it's fully functional, I will have gotten fair value.

The simple fact is, NEITHER the buyer nor the seller in the transaction described in this thread has operated under these sort of principles. So it's hardly surprising that we have a transaction that's gone bad.