I disagree. Now days you can buy a new double for less money than ever before thanx to increased popularity and the market finally opening. I remember pricing out a new Chapuis 10 years ago, I can buy the same rifle right now for $1000 LESS (or better) than I could back then!! Same with other brands like Kreighoff and Merkel! More retailers allows me to actually shop around, with guys that actually have guns in stock. More high volume makers then ever before means more guns to choose from at better pricing due to new high production CNC machining and assembly line techniques. The only time I had previously been able to handle doubles in a gun shop was in the U.S. Doubles were once hard to come by and fetched a premium price. One time I bought a double rifle at a gun show, before I had made it to the door I sold that rifle for a $$$ profit to a guy that just had to have it!! Now days you can just go on the interweb and buy a new one for less cash. Interest in doubles has gone up,,, but to an even greater extent, so have the number of guns available.
The price had definitely gone up on old high end British doubles. It is these rifles that are becoming more and more sought after as the double rifle interest base grows. Of course the number of these guns out there a very limited. These rifles require deep pockets and even hint at being a status symbol, if you follow that stuff...