Seller's market

Oh boy I'm getting in the eBay discussion. I must be really bored. I've been using eBay for a few years now and here's how I deal with it: When I find an "object" of interest, I set a limit as to what I'm willing to pay for it. If the item goes beyond that, I STOP. There is no overinflating prices because I got pissed for being outbid, it's just that someone else is willing to pay more and so be it (I'm cheap). But so far I got some items that I have not seen anywhere else and believe me I search... On another side I once found an item that I had no (read NO) interest in and I had to pay $1 for it to get it because it came with a bucnh of stuff I wanted. I placed it on eBay and got $150 fo it (double of what I paid fo the whole deal of stuff I wanted: about five computers and accessories) I felt sorry for the guy who bought it but I'm sure that he was happy with his purchase (I actually send an extra something with it out of guilt). Now where am I doing something wrong? What would be the ideal system? How can you at the same time make peolple happy and optimize your return? I'm a hobbyist, I don't speculate on value of computers but I want to be able to: 1) Find computers that were not popular in my area and are almost impossible to find. 2) Be able to get at least what I paid for when I sell an item (I prefer trade though). 3) When I find something on the net, have at least a chance to get it if I really really want it. Francois