Not as technically minded as minded as some of the other folks on here but with mine I found rust on the front quarter pannel wheel arch, apparently they are notorious for this, also rust under one of the doors at the central pillar corner, vw wanted 2 grand to repair it however, got a guy to do the same work for 250! Might also be worth seeing the last time the timing belt was changed as it has to be done every 4years and costs around 400 quid.