Dave1: The reserve price on an auction is the lowest price that the gun will actually be sold for. It's a way for sellers to protect themselves from a situation wherein the final bid on an item is lower than their minimum asking price. Of course, I never really did understand why a seller doesn't just start the bidding at their minimum. Apparently though, completely meaningless lower bids are thought to attract attention.
Oh as far as the 686 price.. just to add my reference to the list there. I paid $475 for a 686-5 6" somewhat recently. The was a excellent condition 4" in the same shop, for the same price. They were marked $500 , but the real price was $475.