I think with a "full" or documented service history you can't go far wrong, Listen to it starting from cold and think about knocking noises e.t.c., Terzo(3) 1997 Rally Blue Mica was based on a UK WRX I think, a limited run of 333(no number 13 !) numbered 1-334, should have a numbered "plate" in the dashboard somewhere, Alacantra Sti seats (but not embroidered with Sti logo) gold 16"Subaru wheels, Terzo badge under side repeaters and at the rear. Terzo floor mats, Front fogs/Driving lamps, Air/Con, Alarm immob., not sure about the rear spoiler though, have seen them with the standard WRX low wing and the curved "mid height" one. Have a look at inside/outside tyre wear, regular oil changes a must !! Check that any mods aren't too wild and over stretching the car, OR done properly if there any !! and generally look out for what you would with any car............I hope it goes well for you Mate.