I was kicking around the idea of trading my 36 which is a square butt for one with a round butt. round butts will ( in general) command a premium over the square butt. Both are 36 no dash ... and the round butt has a slightly better finish than mine. Mine is in excellent shape by the way with just a hint of wear to the blueing on the end of the barrell.
Particulars are .... 350. on the round butt. I paid 325. for mine .. & told him I wanted 275. His last offer to me was my gun and and a hundred bucks and I passed.
Like the guys told you above ... dealers are in business to make money. They won't try to recoup lost profit from one gun on the next ... too risky. They have to make a profit on both. As long as its not way out of line you can't complain.