Just run in.
Taken 2 passats from ~90000miles to over 200,000miles.
the old 1.9 engines are far more bombproof than the new 2.0Tdi ones.
Known issues
Electric hand-brake
Diesel Particulate Filter (DPF) – could be a problem on a car like that as they are only averaging about 10,000 miles a year so could be a lot of town driving.
Had one big problem with the oil pump – these are the most elaborate oil pumps you will ever see, they have a habit of the the hex shape bar wearing and unfortunatly if this happens and the oil pump fails than its new oil pump, new turbo and usually new engine.
Look out for high oil consumption.
Had an issue with a sticky turbo actuator unit too.
Don’t let that put you off though, great cars.
Usual stuff – full VW service history, check for signs of premature wear to identify whether it was thrashed or driven sensibly.