What year? Mk4 / Mk5?
Avoid <2000 Mk4s if you can as these were not Pumpe Duese. Revisions to MK4 were new 115 PD, 130 PD and 150PD. All can be chipped, 150 GT TDi can be chipped upto 180bhp and 370nm of torque. 130 and 150 both had 6spd boxes. This is a 1.9litre engine.
Please, please, if you are serioulsy looking here, also look at Seat Leon and Skoda.
Same cars, slightly better VFM
Golfs are seriously well built but they depend on their badges too much. Having said that, a well serviced TDi will see well into the 100ks mileage wise.
Early Mk4s dont handle well regardless of GT badge, late MK4s handle as well as MK5s thanks to 2003 revised suspension.
Mk5s are mainly 2.0litre TDis now, but are crazily expensive for what they are.