The car has only done 155,000 miles. You need to see a full service history with all appropriate cambelt changes done and recorded, full history of brake services and evidence of suspension bushings having been checked and/or replaced. Test drive it and check for any odd happenings. Ensure that Air Conditioning works as it should, plus gearbox & overdrive, engine and drive train. Ensure that ABS works correctly and that booster does not show any abnormalities. Check for odd noises and action from power steering and that electric sunroof works ok. There should be no signs of water ingress throughout the car. If your inspection says the car is great then go ahead and get it after ensuring that the seller will put right any wrongs discovered within a reasonable period (say, three months). The turbo is the best of the 760s (apart from the turbodiesel that is).
All the best, Peter.
700/900/90 Register Keeper,
Volvo Owners Club (UK).