Actual average selling prices for collector-grade 547s seem to be in the high teens, less for a lightly-used specimen, but even shooter-grade guns book pretty solid when they pop up.The current GB prices for S&W 9mm revolvers show that the sellers want stupid money and the bidders aren't biting.
Those guys asking over two G's for one without a box are wildly optimistic.
(I like the guy asking big money for a "Pinned & Recessed" 940 that clearly does not have a pinned barrel, nor ever did any 940 have recessed chambers. Plus the gun has a clearly visible alphanumeric serial number that dates to the early Nineties, a decade after any pinned barrel Smith left the factory. What do chucklefucks even think "pinned and recessed" means these days? Are they just using it as shorthand for "I think it's old?")