I've gotten most of mine in the last several years and I found that the base sets are usually fairly cheap if you look for a bit. The subsets on the other hand can go up dramatically. A few are not too bad but any of the autographs, costume cards or the older stuff will probably cost a little bit. I would just keep checking ebay because most of my purchases were base sets bundle with some or all of the subsets and that can help save a little bit.