Dondo: Before you make the deal find out if you can return it if not satisfied. If the current owner gives you a 3 day window, make sure it begins the day you get your hands on that pistol.
(1) Check for slide to frame tightness - there is nothing wrong with the reliability of a 1911 that rattles when you shake it from side to side. Too much rattle and she may not group well for you.
(2) cycle the action and feel for any binding you may encounter - it will indicate a problem.
(3) Make ablsolutely certain that all the safeties work. Make certain the grip safety fucntions properly, that the slide safety does not disengage all by itself and that the plunger tube spring holds it in place and, that the pistol will stay on half-cock if you put it there (press forward on the hammer to see if you can get it to release under pressure without the grip safety engaged.
(4) Take a dummy round with you, or 7 of them if you can put them together, so that you can test the cycling of the action with a full magazine. Start with the slide locked back, insert the magazine and release the slide release to see if she will properly chamber a round and go fully into battery. If it works on the first round, then manually cycle the action to assure that they all do.
(5) Disassemble the piece and make certain the plunger tube assembly is firmly fixed to the slide. It is only staked in and they do come loose on occassion. If it wobbles or does not appear to be firmly fixed, it can be fixed easily.
(6) take a good look at the barrel. Most will nto have been shot much and the barrel should be in good shape. Look at the outside of the barrel for any unusual scratches or dings (on the muzzle or elsewhere) as they could indicate a potential problem. Also, check the lugs on the top of the barrel for indications of extreme or serious wear, chipping or scratching and look into the slide area where it impacts with the barrel for any burrs, poorly machined areas or serious scratches.
(7) make certain the magazine functions to properly chamber your cartridges and to hold the slide baack after the last round.
(8) make certain the trigger has a smooth pull and a crips let-off. For far too long, the colt factory department head of the pistol section bragged publically that no pistol would leave his shop with anything less than a 13 pound trigger pull - if you have one of those, it can be fixed very easily.
(9) take it out and shoot it and see what kind of groups you get. You should be able to group 4" at 25 yds or better with ball ammo. If your groups are way off, either off center, high, low to too large for your preferences, get an Ed Brown drop in barrel, it should close up your groups to 2" or less at that distance.
(10) if she bites the hand that shoots her then you will need a beavertail grip safety to avoid her little love nibbles. Get a King's no gunsmithing drop-in beavertail safety - I have two and they are excellent for the 1911.
Then, after all that, have fun. This be Mikey.