In all my years of collecting, buying, selling and just wanting...the SAA is the only gun that I've ever bought for pure speculative investment.
I've paid more than I should have, but then, the person that I sold to paid more than they should have.
The SAA is the exception to the rule, when it comes to buying and selling based on the Blue Book.
I have seen 40-60% guns go for 90% prices, simply based on a dubious "provenance", as in personally carried by Duck-Bill Hickok or Custer or some other silly shit that no one can realistically prove.
I think you'll find that Winchester lever actions also can engender that exception also. I once went to a general antique where they had ONE gun included. It was a Winchester 1873 rifle. It had only one thing unusual about it in that it had a single-set trigger. At the time a realistic market price for that rifle was approximately $275 as other versions with normal triggers were selling for $225 or so.
When that Rifle came up the auctioneer said "We have a rifle, it says 'Winchester' on it."
Suddenly, there was a rustle of whispers going around the audience of bidders. . . "Winchester?" . . . "Winchester!" "Winchester!" "Did he say 'Winchester'?" "What did he say?" "What was that, was it 'Winchester'?"
Everyone there had had just as much of an opportunity to look at that gun as everyone else and could have even handled it.
Every lot up to that point had an opening bid of $5. . . but the auctioneer asked for an opening bid of $500. . . and there were paddles up all over the audience! When the final sales gavel came down, the final bid price, not counting 10% buyer's premium and sales tax was $2250, more than 8 times the real value of the rifle!