I've had my golf for nearly 2 years and haven't had to do much with it. I had corroding inner alloys so had to get all my alloys re-done so they look new and good. Recently my exhaust split from the back box due to corrosion so today I had a twin scorpion from Demon Tweaks, my friend also helped talk me in to getting a dump vale and air filter (helped pay for it). It sounds much sportier with these new things on it! It makes the psssh sound and feels somewhat quicker on the accelerator.
The next things I plan in the future are perhaps some new breaks (mine are squeaking a bit) – how much are they for the GTi? And who knows, maybe even a remap?