dont see why people say that mk4s always go wrong, in 4 years of ownership the only things ive done are:
window regulator clips (fair enough vw should have made them metal not plastic, but the new revisions have this sorted)
exhaust (exhausts tend to go on older cars)
clutch clip (again vw should not have made them from plastic but i belive the new revisions have this sorted)
then usual consumables like tyres, break pads, bushes etc. out of all my mates i think ive had less problems with my golfs than theyv had with any of there cars.
good luck when buying

*notice my sig* hahaha