I have no problem with buyers suffering some sort of punishment or penalty for non paying, be it a small fine, a suspension, or what about where feedback is positive neutral or bad, what about a 4th section showing how many NPB strikes you have had over a period of time.

However what is good for the goose is good for the gander, if something like this came in for non paying buyers, the same should be done for non performing sellers, a fine or a suspension or a visual indication of how many times they have refused to complete a transaction on their feedback page.

The traffic needs to be both ways for buyers and sellers not just one or the other. And as for your time you might loose dealing with a NPB , the same can be said about non performing sellers, they take up time by waiting for an auction to close in which time you are not bidding on the same item that might come along elsewhere because you have committed to one auction, and my time and stuffing around is just as valuable as a sellers time.