Before driving, however, make sure you are insured to drive it then, if possible, take it on a drive that covers a mixture of conditions i.e. fast motorway driving, slow urban driving, twisting roads - and don't forget to check reverse.
If it's a 4x4, go off-road, and make sure you drive in four-wheel-drive, low and high range.
Always inspect the bodywork in good light.
Look for corrosion or rust. Rust is probably the most damaging thing of all on cars over five years old. Surface blisters can be relatively harmless and easily treated but corrosion coming from the inside of the body panels is more serious.
Look for rust at the top and rear of the front wings, along the side sills, below front and rear bumpers and the bottoms of the doors.
Sometimes a rust blemish on the paintwork can indicate more serious corrosion underneath. Press the panel gently with your thumb. If there is a cracking noise it indicates advanced corrosion.
It is usually not worth repairing rust that has perforated the bottom of doors, the bodywork around the front and rear screen rubbers, on trailing edges of boot lids or tailgates and leading edges of bonnets and on rear wing panels.
These can only be repaired expensively by specialists and subsequent painting is costly.
Walk around the car and look along the doors and wings from each of the four corners. Any crash repairs will show up if they have not been well done. You will see ripples or a change in the texture of the paint if there is a lot of body filler underneath.
Take a small magnet with you, it will be attracted to metal but not to plastic body filler. Look also for variations in the paint colour.
Water stains in the boot, around windows, on carpets and around the sunroof opening may indicate leaks.
Look for rust perforation on inner wings, the bulkhead and any cross members and chassis members visible under the bonnet. If you see any, reject the car.
Beneath the car check side sills, chassis legs, cross members and sub frames. Tap suspicious areas with a lightweight hammer, or push hard with your hand to detect the "give" of weakened metal. Be wary of freshly applied underseal - could be hiding weakened metal.
Check the floorpan for corrosion.
Look at brake pipes, if they are crusted or pitted with rust, these could be dangerous.
Check suspension and steering mounting points for serious corrosion, especially under the bonnet.
A car that has been in a collision can be dangerous, especially if its suspension and/or steering have been damaged.
Examine under the bonnet for damage, creasing or replaced inner wings (unsightly welds are a give-away).
Also inspect the engine bay forward panels and forward chassis legs for repairs or creases.
When test driving the car the steering should be consistent with no tendency to pull either left or right.
Look under the carpet between the front and back doors for signs of welding or repair in case two halves of different cars have been welded together (cut and shut), which is extremely dangerous.
Unless you're totally convinced the car is in good condition, take it for an AA test.