Make sure any low mileage TT has been driven frequently enough to keep the turbo's seals lubricated. I have a '95TT with 40K miles that I have owned since new. We were "snowbirds" for 8 years and the car sat in the garage each summer. At 9 years of age (about 20K miles) the turbos had to be replaced as they started smoking badly. I replaced them with Sport 500's. Now, about 9 years (and 20K mile) later, one has started leaking and both are out to be rebuilt. Make sure you have a pro look at the turbos on any car you buy.