Value is all in condition, originality, story, and buyer. It is worth what someone will pay for it. If you had some documentation, such as a picture of your dad, snatching that pistol from a Kraut, then that would be worth a small fortune....again to the right buyer.
I was involved with the early GWOT, if I had a Tabuk Sniper, with a picture of me after I got my hogs tooth, with a pic of the tango and his gun, the sky is the limit......it just so happens I have a Tabuk, but no pics, and therefore, market value is much lower.
Man I wish the rules were like the days of WW2 and Vietnam, I would have an arsenal.