[thstone]

You need to worry about all of the problems that can't be tested because the engine doesn't run. For example; cooling system, power steering system, exhaust, air conditioning, emissions system, almost all of the electrical system, etc, etc.

Step One in buying a roller is to bring a spare charged battery and install it so you can test as many of the electrical systems in the car as humanly possible - wipers, fans, displays, dash, lights, windows, top, seats, alarm, fob lock/unlock, stereo, etc, etc.

Step Two is doing a full PPI inspection on the body, suspension, and the rest of the car.

I say this because when I bought my 1997 Boxster, the seller swore that the only problem with the car was a failed engine. He promised everything else worked perfectly. It still cost me more than $1,000 beyond replacing the engine to repair all of the problems that the seller promised didn't exist.