I always buy the current Blue Book, as well as Supica's Standard Catalog. They're worth the $40 or whatever I can score them for... Keep 'em in my truck, you never know when you find a cool little gun shop you've never been to before, and for us old guys with time on our hands, our weekly rounds of the usual places.
I'll usually accept a price maybe 10 or 20 percent above the books' top prices, because in my region, used firearms of good quality typically command a premium.
I dunno, maybe it's all the rain, but we sure have a lot of knowledgeable gun collectors up in the PNW.
If nothing else, one gets a lot of good info, especially production history, military and law enforcement issue and usage, variants, etc., on the firearms -- and both I mentioned are well-researched and arranged excellently with great photos -- but mostly, because one can get a very good idea of what NOT to pay for a used gun.
Frankly, I gave up on looking at what guns sell for on the auction sites, because any gun I would want, ends up with a winning bid that's usually just stupid. I base my valuations on the books, LGS prices at the reasonable stores, asking prices on our regional firearms forums and the little knowledge and experience I've acquired on firearms and their values over the past 45 years of buying and selling...
One thing is also good to note: do your research into the history of the model you are considering purchasing. Even the reputable makers put out clusters of lemons just bad guns in certain years, and you can also easily find out from experienced gunsmiths (and to an extent, occasionally from long-time gun shop owners who aren't totally brand-biased) what a model's quirks, foibles, and durability, reliability and breakage history has been over the years. Often, you'll find out that a particular model might not have as great a track record of a variant of the model put out in the same year or different years.
Absolutely positively a wealth of info!
