That price is probably not bad, if everything on the car works. You can check natomessageboard.com and compare their for sale section.
Things to check:
Excessive oil in the intercooler
Clutch/Transmission shifting quality
Check for full boost, leaks at this age aren't uncommon, turbo quality
Check all the interior power switches.. some like to not work with age such as the auto ride switch and fuel octane switch
Make sure the seat back isn't broken.. this happened to a good number of cars, but fixable
There's more things you could check, nato has some good resources.
a black car.