I recall someone asking if he had paid too much for a rifle. The response was, no, he'd only bought it a couple of years too soon. Having said that, one should be EXTREMELY careful buying a piece because of markings. There are a LOT of spurious SS items. I have never bought a really expensive piece. I suppose that if there was something that I really, really wanted I might, but even then I would have to be confident that I could get at least most of my money back if needed. If nothing else, estate planning has to be taken into consideration.
I've seen auction reports with astronomical sales reported. Want the sawed off 10ga. Greener that Doc Holiday used at the OK Coral? With provenance? Sold for $68 000 if I remember correctly. The '66 Winchester used at the Little Big Horn by the Cheyenne who in later years painted the pictograph of the battle on a hide, whose cartridge casings were found on the battlefield and matched to the rifle by forensic analysis, so it is known where he was and where he fired? It sold for less than $100 000.