1.9 PD engine has good reputation if serviced correctly and correct oil used. It should have a cambelt soon-ish plush precautionary water pump change- if not already done at 40K. Check rear tyres for unusual wear on inners, can lead to lots of noise. Check all the electrics, central locking, etc and air con as VAG electrics can be erratic as they age. Check right through car for water leaks and damp carpets, VAGs still leak after all these years. Can't think of much else apart from test drive and usual stuff.