Don’t sign anything before you drive.   If the owner won’t let you drive it or inspect it carefully, he’s probably got some thing to hide, and hidden things will end up costing you money.
     Use your eves for more than admiring a low price.  Check for rust, especially in hidden or hard-to-see areas of the car body.  A car that’s starting to rust probably indicates a car that was not affectionately cared for, and may indicate more serious problems, especially if attempts have been made to conceal the rust with fresh paint.  At the very least, rust lowers a car’s resale value.
     Open the doors.  Open the hood and trunk lid.  All should open and shut easily.
     Climb in the car.  Sit in each seat to check for things like broken springs.  Look for tears in the headliner, worn carpets, missing floor mats, worn pedals, or missing control knobs.  Any of these can indicate hard usage.
   wPush, pull twist and slide.   Every control on the dash.  Otherwise how will you know if they all work?  and don’t forget to try the heater-even if it’s summer.  Check all lights.  you’ll have to fix any that don’t work if you buy the car.  Check the tires, including the spare, to see if they’re badly worn.  If any have to be replaced, that’s extra expense for you.
     Check the shock absorbers.  Stand at a corner of the car and repeatedly push it down.  Keep doing this until you’ve got that corner of the car rocking up and down virgorously.  Then realease your hands on a downward push.  The car should rebound once and stop. If it continues bounding up and down, that shock is bad and must be replaced.  Repeat this test at each corner of the car.
     The engine shuld start quickly and idle smoothly.   An engine that is hard to start is an engin tht needs work done on it.
     Raise the hood.  Check the oil level.  If the oil level is low, that may indicate an oil-burning problem.
     Rub your fingers across the dipstick and feel the oil. It’s okay if the oil is dark; that’s normal after a few hundred miles, even with fresh oil.  But if you can feel sludge and grit with your fingers, that’s not normal.  That can mean a lot of things, none of them good.  Also if the oil is extremely thick, that can mean a heavier oil has been added to conceal knocks and squaks the owner doesn’t want you to hear. 
     Check all the fluid levels.   If any are low, that means, at the very lease, that the previous owner didn’t pay much attention to his car.   At worst it can signal an expensive problem. 
     Take the car out for a drive.   Check the brakes when you’re driving.  They should not pull the car to one side when you depress the brake pedal.
     Find a level, isolated stretch of raodway.  When you release your grip on the steering wheel for a few moments, the car should not pull to either side.  If it does, this indicates a wheel misalignment problem.  Also there should be no shimmy in the front end or vibration in the steering wheel.
     Find a bumpy section of road..  The car should not “bottom” as you ride over bumps.  Nor should it sway excessively when traveiling around smooth or bumpy curves.  If it does, this indicates bad shocks.
     While traveling along an isolated level stretch of road at about 30 mph, release and depress the accelerator quickly a couple of times.  Listen for noises.  If you hear any, especially coming from underneath and to the rear, this may indicate excessvie wear in someparts of the drive train.
     Check the automatic.  In a used car with an automatic transmission you can tell something about the condition of this improtant unit  by niticing if the car accelertes properly on a normal upgrade.  Slipping is cause for futher checking.  In addition, try backing the car up a short grade to see if this action is smooth.
     An automatic transmission should shift smoothly.  There should be no clunking or jerking as the transmission shifts up or down.  And the transmission should not “hang” in one gear for an excessive amount  of time.
With a manual transmission, or stick shift,  notice how far in you have to push the clutch.   If it goes in all the way, there isn’t much clutch left.  The pedal, however, should have about an inch of play when it’s completely released.
     Remember, when you’re buying a used car, any parts that require immediate replacement add to the cost of the car.  Unless the seller is willing to slash the price to allow for this cost, you’re going to end up paying a lot more for the car than you should. 
     If in doubt about anything, have a mechanic check it out.  The few dollars he’ll charge can save you a lot of dollars in the long run.
     When you buy on the installment plan,  have the seller put in writing all the terms of the transaction, including down payment, monthly payments, interest charges, etc.  All repairs and accessories that are promised to you should be itemized on the bill of sale or contract and should be acknowledged by the seller’s signature.  If you’re offered a service gurantee, make sure you understand it, since such guarantees can be trickey, seeming to mean one thing and actually meaning another.
     After you have made a check-list of all of the above and you are satisfied that this is the deal of the day, get behind the wheel and enjoy the ride!