Lousy title but which makes have you seen with the highest price hikes in the past year or two? Colt, S&W, some foreign make. Not just talking one or two models but as a overall brand. It needs to be something 20 year or older, not anything recently made in the past decade. Take USGI marked ones out of the mix because they really are in their own niche.
Personally, anything made by Colt in the 50s, 60s, and part way through the 70s seems to have been on the rise, and earlier one's tend to be highly sought after. Same with S&W older revolvers. What used to run $300 bucks or so for a nice S&W K17 now can easily fetch double that or more and that is just in the past couple of years.
What have you seen as far as what interests you and have really seen the prices jump?
I kick myself in the arse for not buying more older revolvers back when you couldn't hardly give them away because of the semi auto craze going on.