I pretty much agree with PaigeOlivers strategy.
I mostly bid on toys and games that I had as a child. I always bid what the item is worth to me and that's all. If I get the item, great! if I don't, then I try again next time.
Except that I rarely bid on HighDemand, Uncommon Items, because I know the prices are going to go higher than I want anyway. When I do bid on these items, I usually wait until the last 30 minutes or so to bid.
Many items that I want to bid on are so rare, that they only pop up two or three time per year, so I am used to waiting. Luckily for me, many of them are so rare that no one else even remembers them and the demand is low.
A few of the things that I have gotten great deals on are:
Bing, Bang, Bounce by Ideal. Almost no one ever had this game.
Sears Remote Control Tower Crane. Very few people had this either. I bid on 5 of these over two years before I got mine.
Sears Highway Police Chase set. Aain, it took two years to finally snag one for under $40.00
Twix by Avalon Hill. For some reason this auction fell threw the cracks, and I got it for $15.00. I had seen several go for $50.00 or more.
I have won a few auctions for HO scale slot cars, but that is a market within ebay that has gone just nuts. It is full of sellers with very common cars and buyers who will pay anything to get them.