Another thing I always look for is a shaved bridge and a low saddle. Tell-tale sign that the guitar needs a neck reset and the previous owner didn't want to spring for it and instead used the stop-gap method of shaving the bridge. So then you have to factor in the neck reset costs, and a new replacement bridge and saddle. I purchased one of my guitars with this problem, because it sounded and played so well, and I figured it was worth doing to protect and maintain it both from a playing standing point and from an investment. The neck reset and replacement bridge/saddle gave it an even stronger bolder sound, and enhanced its playability.

Some are a little squeamish about buying a used guitar in this condition, but usually you can haggle with the store (or the seller) on this point and get a price break if you agree to let the luthiers in the store do the work (making sure they're reputable and know what they're doing,) and in the vast majority of instances, having this work done should not detract from the sound or playability in any way, and, protects the investment.

It's rare to find an instrument new or used that is perfectly setup to your specifications right out of the shute, but if it's close to the way you like your action and intonation, a minor tweak (setup) is not a big deal.

My main sticklers are buzzes, intonation and lifting or worn frets that cause your pinky finger to catch on the side edge of the frets when you're doing a slide. If any of these three can't easily be remedied, I pass, and look at something else.

Also, I have a major problem with large or long cracks, whether repaired or not, and no matter how stable the salesguy tells me it is. Pickguard crack isn't a big deal. It's those long ones in the sides or back, and the big ones in the top repaired with splices or down the center seams. Tells me the instrument's been abused (and no I'm not going to put a Lester Flatt or Josh White sized pickguard on it.**BG**

And always have the store give you a light and a mirror and clearly show you the inside to check for structural problems, repairs or modifications to bridge plates, kerfing, bracing, etc. The insides sometimes tells more of the story than the outside.