Sometimes, eBay auctions go sky-high just because someone Really Really wants whatever it is for sale, and there's nothing you can do about it except watch for the next auction to come around.
A couple years ago I restored a little Suzuki minibike. I bought some parts for it on eBay and usually stuff sold for fair prices. Once in a while, though, this one guy would bid on the same auctions and when I saw his name on the bidder's list I'd just give up, because I'd learned that he would pay whatever it took to win. One time we were both bidding on a rear view mirror; as I watched the last seconds of the auction the price went from around $20 (about what it was actually worth) to $125! All for a stupid rear view mirror for a minibike.
I figured if he wanted it that bad he could have it, it was no skin off my nose. I ended up buying two of them for $20 a couple weeks later, so it worked out fine in the end for me anyway.
