what governs the stock market...greed and emotion, same going on here. A feeding frenzy.
Six years ago you could buy multiple working Jeffrey 450/400 doubles from Bob at Westley Richards or Cape Outfitters for $6,000. Three years ago they were $12,000 and now the prices today are mid $20's, though some ask 40's
The ballsiest flip I've seen lately is the H&H 500/465 that was bought on Gunbroker, or another site for 40,000 and now re-priced at 69,500.