If the owner/dealer agrees, check your yellow pages for mechanics specializing in diagnosing used cars. Most automobile clubs have a diagnostic center that will evaluate your car for a small fee. (Think of the fee as an investment in getting a good car.) 

If the owner won't let you take the car for that long, there are mobile diagnosticians who will come to wherever you want to evaluate your car. 

The technician should:

• Perform an engine compression test 

 
• Check spark plugs and ignition system 

 
• Perform a contamination diagnosis of oil and fluids 

 
• Check transmission fluid 

 
• Check fan and belts, charging system, power steering and air conditioner 

 
• Check cooling system: radiator, heater, by-pass hose 

 
• Check braking system: lining, wheel and master cylinders, drums and front disks, hoses, bearings, grease seals 

 
• Check suspension: ball joints, tie rod end, idler arm 

 
• Remove differential plug and check lubricant 

 
• Test drive the vehicle