Me and my friend are buying a second hand guitar sometime soon and we're collecting it ourselves.
i'd like to know what things I should be checking for before handing over the money
(apart from the obvious things like...make sure it has 6 strings and some pickups)

thanks everyone
I wouldn't worry about it having strings, seeing as they can be replaced... Check the neck, it could be warped - not good.
Check the neck, the nut for wear, see if the bridge is worn out, check the hardware for rust. check the frets as you dont wanna have to refret it! If it works then thats a good sign. If you do buy it ide probably go down you local music store and hae it checked/set up properly!
gd luck
The Official "Rockin' Roadie"

-Lakland Skyline 44-02
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The condition of the surface should give you some clues as to how well it's been treated, but don't be afraid to have a really close look for any serious damage, particularly around the headstock and the neck/body joint.
Take a tuner with you and check the guitar's intonation. Check the action. Check the frets.
Plug it into an amp and test all switches and volume/tone pots.
Check over the hardware, tuners, pickups, bridge etc - look at the fixing screws (if the heads are all chewed up, someone's had a screwdriver to it time and time again).

That's all I can think of. But don't let money burn a hole in your pocket and don't buy unless you are sure. If you can, take someone experienced along with you.

Hope that helps.
Check the Neck and the Bridge.
Most of the times the guitar is ok , a good luthier can bring the joy back. So if the guitar is with bad intonation and etc... ask for a discount because you will have to send to a luthier.

Good bye dude.