Can Just A Couple Obsessive Collectors Drive Prices Up In Particular Areas?

I agree with the last two posts, but I think it takes more than "a couple" of collectors as in the title of the thread. More like at least a handful.

My reasoning: If it is just a couple of collectors, then you only have a bidding war once on any given item. The next time it comes up, there is no competition (because the other collector already has the item), and the price drops back down.

If there are items that only come up for auction once or twice per year, and a handful of collectors want it, then I think you have a situation where competition can drive the price up for some time. I, too, have seen this on a few coins where I searched various archives for the selling price history over the last few years, but when I bid recently, the auctions ended around double what I had expected.