Mk1s are getting very expensive, even for rot boxes or base models. The GTI only came in 3door and with either the early 1.6 8v engine or the later 1.8 8v. Avoid Mk1s with sunroofs as they are most likely to have rust or leaking problems.
Mk2 is much easier to get a decent example.
Is 2k your initial budget for the car or do you want to buy some other stuff (suspension/engine) with that cash?
For that budget you'll probably be looking at either a Mk2 non-GTI model with lower miles (sub 100k) or a higher mileage GTI.
You probably want a clean unmodified example. One thing to look for, if it's a pre-89 model it should have small bumpers, after then it should have big bumpers.
As said, get the best, straightest body car you can. Everything else can be upgraded. For example, even if you buy a GTI you'll probably want to replace the brakes with newer better ones (from a Mk4 perhaps). If the engine and gearbox are ok, keep them in for the moment and upgrade later once the rest of the work is done (unless you have space and money to get it all out and done in one go), then at least you can move the car around easily.
