Not a lot to check really. All the usuall stuff when buying a car. Check haldex IS working by going to to some grass and giving it some welly lol Make sure haldex has been serviced every 20k. It goes oil at 20k then oil/filter at 40 k and repeat Make sure servicing has been done properly as some garages even VW don't realise that haldex needs doing and has a different oil to the rest of it, and it has been known for them to drain the rear diff and replace with haldex oil!!! They eat the inside edge of tyres but that's down to giving it beans round corners, which you will love as it really grip