Ebay

Have you ever tried to win something on ebay, but only to be out bid by another person by only a few cents? Well that has happened many times while i was bidding on ebay. If you notice ebay is somewhat of a free market. I've noticed that most of the bidding is done in the last few minutes and seconds of an auction. I was thinking about selling stuff on ebay and would like to know what some ideas as to what you think would sell for about 3/4 thier original price or better.