OK, number one, HPM100s go for a ton of money on eBay, period. Number two, there was a thread about these the other day where someone said they go for over a grand, which is a ton of money. Number three, the $1300 ones on eBay are local pickup only, meaning they could be worth a TON more but the buyers may not be local. They're also in fairly poor condition. Number four, my guess is that these estate sale HPM100s are underpriced. Were I local, I would've been there with cash already.