Check rear tyre wear on the inside edge, poor tracking causes feather edges and rumbling like a wheel bearing away.
Check service history with correct spec oil (VW504/507 - 5w 30).
Should've had 2 cambelt changes by now at 4 years each. If going by mileage it's every 80k miles.
Listen for turbo "Owl" noises when playing with the throttle. Not really a major problem if it's fairly quiet as they all do it when they get some miles on, but you can use it as a bargaining tool.
Visibly check turbo boost hoses to see if there's any sings on them having slipped out and been refitted. Down the front behind the radiator is where mine popped out (coincidentally just after the Seat dealers had been in there and checked the flywheel on a recall).
