kdr - "simple engraving" means house pattern? Send me a email address if you run Excel or a land address if you don't and I'll send you a file on Brit/Continental pricing. My prices are typical market for USA retail of a 12 gauge SxS made in the 1890ish to 1960ish time frame. It uses factors of maker's name for Brand Value level, gun model for Original Quality grade (not all Purdey/H&H are best guns), and an estimation of Current Condition. The pricing is a fairly straight forward 3-D matrix - we just don't see guns placed in the matrix order, so pricing is a bit of a mystery to most people. Dealers, collectors, and trade students see enough guns to develop an intuition about price.
I very much agree with Small Bore's pricing. I'd add that for $40,000 you can buy a pristine example (takes longer to find, but they do come on the market) and, should you decide to go mizerly, for $5,000 you can buy a gun that will need a lot of money spent on it to be satisfactory.
Dig, new barrels always beg the question of what happened to the old ones and suggest that the gun has been shot excessively. The market is alarmed at the possibility of wear to lever work, hinge points, and locking surfaces - these are the easiest and cheapest of things to fix. The costs of real barrel work (beyond refinish) and real wood work (beyond repair/refinish) are usually underestimated and the cost of mechanicals is usually overestimated.
