You can always set a reserve price. Meaning, if you know you don't want to sell it below, say $100, you set the reserve at $100 and it will not sell unless someone bids over this. The reserve is private and the bidders can't see what you've set it at. But, it will say 'reserve not met', if the bidding is to low. I've sold things and bought things off of e-bay and have had no problems so far. You can also set a 'buy it now' for the price you want.