Always shop gunbroker.com first to get the typical selling value (not ASKING value) of guns in various conditions.
Gunsamerica.com tends to have higher asking prices, while gunbroker is more representative of the better deals you can find.
With a little net research you might be able to find a FFL that will transfer for free in your area also. And of course there is no tax if you buy the gun from another state.
Mauser Werke, Schmidt-Rubin, Colt, Walther, HK, Weatherby, Browning, Ruger, Beretta, Savage, Bushmaster, Marlin, Mossberg, Remington, PTR, Saiga, S&W, Sig Sauer....a few friends of mine