Check that any GT2 is what it claims to be by comparing underbonnet codes with the VIN plate and service book.
A smoky exhaust (once warm) suggests worn valve guides. This can result in a £3000 bill to replace them
Take the space-saver spare out and check the floor beneath it for the ripples or repainting that suggest accident damage
Check for rust in the windscreen surround area, especially below the screen. Peel the rubber back where you can to look for bubbles.