I have bought several collections in the past year, with the intent on selling most on eBay. IMO, Craigs list is the place to find the deals, not eBay. Maybe some of these dreamers out there looking to get crazy prices for their collections make buying a new master set seem like a fair comparison. But trust me, for ever 10 folks out there trying to get out from under their tool debt by selling at a crazy high price, there is one guy who has good stuff and really wants to sell right away. At a better than reasonable price. But negotiating a fair price is the key to getting a good deal. I will price out each piece in a collection individually, then add it all up, to make sure I make the right offer.
People have all sorts of reasons for selling their tools, not all involve a shortage of cash. I bought one collection of all pristine Snap-on stuff from a contractor who had two new Mercedes in his garage. His reason....there's nothing left on his cars that he can fix, and he already had another set at his shop.
But there are also lots of motivated sellers, too. The last guy I bought a large collection from was in serious trouble financially, was selling pretty much everything he owned. He was VERY happy to get cash from me, as he said it would have been only a matter of days before the sherrifs came to confiscate everything, and the cash gave him a decent price and avoided that visit from the sherrifs. As much as I felt sad for his situation, I did not twist his arm at all.