Imma be helping a freind look around for a new-used car just wanna know what things i need to look out for besides mileage, weird sounds, bondo jobs, etc.
leaks, signs of abuse. check compression, see if basic maintenance parts have been changed(air filter, plugs, wires, etc)
If you and your friend aren't so savvy with cars, then after you do your first look at the vehicle and he's thinking about it more seriously, get it inspected. Typically a good licensed tech will spot problems immediatley and these are things you can use towards the asking price. Run a CarFax, you can always get one for free from someone on the introweb
Check all the usual suspects. Check oil for color/smell. Black/burnt smelling means the whole car has probably not been properly maintained since Oil changes are one of the easiest things to do. Check tranny fluid (if auto). Should be nice and pink/red, if burnt looking, tranny hasn't been serviced, could be on it's way out. How does the car look for it's age? Some ppl just don't care about their cars, for them its a object to get them from point A to B. If the car looks old/faded, saggy etc for it's year, then stay away. Ask for service records, receipts for work done. remember, they can say oh ya it had brakes, full tune up, and bearings done, but if he doen't have receipts for those, they're worthless. Take it for a test drive. Fire it up (make sure it was dead cold before - Check for Blue smoke on startup. Valve-seals go bad especially on Chevs. Listen to the motor, is it running strong, if EFI, does the idle surge/drop, carbed, does the choke work properly? Any knock or piston slap? Take it down the street. Turn off all fans/heater, radio etc, close windows and listen. Any low continuous vibrations/sounds could possibly be worn out driveline parts. Sounds that are consistant with speed are usually driveline related. Sounds that are consistant with RPM are engine related. Test brakes, good pedal feel or do they go right down or close to the floor. Any rough vibrations/grinding or pulling under hard braking? Test all interior features, windows, door locks, all gauges work, etc. I always look at the interior of a car to gauge it before i get under it and look. Most times, if the interior is clean, there's a good chance the car has been maintained as well. By don't go just by that. If it all seems good, Best thing you can do is take to a mechanic and plunk down $50 or whatever to have a pro mechanic look at it. He can put it on a hoist, check ujoints/CVs, exhaust, steering components, brakes etc.