Some other random thoughts about this
As an example of my thinking....I recently bid on a LNIB Model 64 early model made in 1973 with very nice box, papers, tools, etc. I asked on this forum about what it should be worth. Only one person posted a reply saying around $400-450. Well, if you buy this gun new from factory the MSRP is close to $600 with the MIM, Lock, no pinned barrel etc. I ended up winning the bid by paying $560 for it. My theory is...that if a brand new one is supposed to be close to $600 then a like new used one with box and papers, etc should be worth about as much because of the 40 years older and higher manufacturing standards/quality plus the fact that there is at least a tiny bit of "collectability" so-called because of the age. So, I think I paid a fair price for the gun and I am happy with it. Plus, someone else out there wanted it badly enough to bid $555 for it. If I want a gun and I have the money and I do not think I am going to find the exact same high-quality item in the near future than I buy it. As someone pointed out above, if I am happy with the gun and price than that is what is important.....not what someone else thinks I should pay.