If its a great car, take it to a mechanic.
It should have all records (receipts) showing all work done from date of inception, all parts replaced, all oil changes, etc. Run the VIN # against carfax, as well, to look for salvage issue.
my opinion, a "Performance" vehicle with that age and miles is probably gonna be ragged out. Go buy a car that an old fart would have owned and taken care of instead of thinking performance.
more than once i've been bitten by the "cheap speed bug" and ended up with a basket case.
Turbo's last between 100K-150K dependent on the care of the turbo, oil changes, air filter quality etc. Using a turbo timer, changing your oil every 3K, using synthetics, k&n cleaned regularily you're gonna see near the 150K range for a turbocharger. Poorer maintenance expect to see more issues and shorter turbo/engine life.
there are good chances if it hasn't been replaced it may need to be soon.
Good luck, i'd personally avoid the car if you don't have the cash or "credit" to make sudden large repair bills.