Welcome mate,
Start with this guide (in two parts)..
http://sciroccoregisterforum.co.uk/faq/ ... guide-pt1/
Try and have a good feel/check round the wheel arches under the body kit for integrity. Very hard to determine actual condition so take your time going round the inner lip of each arch. of course it's going to be easier to change the front wings if the fronts are rotten.
Also Entire fuel system can rust from filler neck, tank, fuel lines all the way to Combustion, Does it start from cold and idle fine? How is the fuel pump under the car (I am not an injection expert, someone might add their views?)
Overall body condition? Rust at rear number plate lights? Bulkhead where the clutch cable comes through can quite literately give way.
Finally Sun roof? An after market pop up style to my mind is not desirable, as long as it doesn't leak I suppose.
get some pictures up via a Photobucket account or other.
Cheers