For 350 its worth it. Rather than the regular diatribe of slop, here are some of the pointers you asked for. 742s are a case to, and of themselves, though people here seem to be ignoring that somewhat. A couple of pointers your buddy should look at. Remington kept upgrading the 742 over the years, tweeking with various problems, and the key thing IMHO is to try and make sure your getting a later 742 with some of the upgrades.
Things to check: ask to see the triggerguard out of the gun, its easy enough to be a legitimate request. Then check out the inside of the action, is it badly worn (lots of bare or rusted metal - bad). Look closely in the middle of the reciever, in the channel that would be along the top of the rifle, where the scopemounts are screwed on, do you see deep(say half to 1mm) sets of dents in the sides of that channel, from where the bolt head would be overrotating and hitting it? Dont worry about very shallow sets, or the usual deeper set at the very rear of the reciever (unless they are blatantly obvious and quite deep).
Does it have a firing pin return spring? Some do, some dont, you want one that does. You can usually tell once the trigger group is out, by pushing in on the firing pin, it should feel spongy, and push back out.
The other key issue is the bolt head locking bar, this locks the head into a fixed position on opening to prevent the early issues of bolthead over rotation and impacting of the locking lugs onto the receiver (when the dents get deep enough, the bolt head tried to 'engage' them, and threw the guns timing off, causing jams etc). The bolt head locking bar was upgraded by remington on some of the early guns, but had a 'permanent' fix on later guns.
Those are the issues particular to the 742. Additionally, the original mags are garbage, the newer ones tend to feed much better and more reliably.
Ultimately it comes down to the owner, if like most 'gun owners' he doesnt know his ass from a hole in the wall, and doesnt have the apptitude to work on his own guns, he should skip the 742. They are easy to work on, easy to make run reliably, easy to take apart and reassemble....if you are willing. If you arent, forget it.
One last comment, the 742 is like everything Remington has ever made, junky, just like the 700 and 710. The difference is people expect that you will have to 'fix' your 700 etc, but get all flustered about the 742s, which are usually more easily tweeked than the junk Remington is making these days.
You old man you, go buy a 742 now would ya.
