Same experience here. Here is an example: buyer buys a $280 frame and asks for a refund because the BB threads are messed up and that is what his bike shop told him. They tried everything under the sun and it did not work.

Well, what can you do, you tell him to send the frame back for a refund. I receive the frame and it is Italian threaded as stated in the description, perfect threads. I ask him what BB he bought for the frame he describes an English threaded BB, of course it did not work. He doesn't care because you are screwed whatever you do.

1- You refuse the refund, PayPal claim
2- You argue , PayPal claim
3- You want to send it back he'll refuse and you'd be out the shipping cost anyways.

I mainly stick with Ebay for now because there are very few ways of getting the kind of visibility and the price levels Ebay provides. This site is a good example : sellers seem to struggle selling items for prices that would be bargains at those prices on Ebay.