I am looking at a 91 TT tomorrow. I have been told to do a compression test and see if all the cylinder are the same. If they are great. If one is different put 2 squerts of oil in there and do the test again on the low pressure cylinders. If the pressure goes up the piston rings need replacing on that piston. Also I have been told by a Nissan mechanic to rev the engine quite hard and get some one to listen to the turbos. If you hear a clicking noise in any of the turbos, dont bother with the car because the rotorblades of the turbos are catching the side. The Price, well I'm in the UK so I can not say about the price but you should always haggle.