Take a peek just to the left and below the intercooler - at the turbo, itself. If there is an aftermarket downpipe attached to it, make sure there is/was some type of Stage 2 tune on it, or at least make sure you'll be able to get a Stage 2 tune on it relatively quickly after you purchase the car.
If the stock turbo heat shield is still in place, none of the bolts holding it on look like they've ever been touched, and the heat shield itself is not obviously physically cut, you're probably in good shape. If there are signs of tampering, you're probably still ok - just know that at one point the car probably had an aftermarket downpipe on it and was hopefully flashed with some type of Stage 2 tune. If there is an aftermarket downpipe on the car, you're probably still ok as long as you can flash the ecu to some type of Stage 2 tune relatively soon after you purchase the car.
Other than that, it looks like you've found a pretty clean car. Have you been able to test drive it yet? How does she ride?