Get a 16v if insurance allows. Running costs are pretty similar for 8 and 16vs.
Read back through the mk3 section for common problems and faults. There is a big issue with stalling, cutting out juddering etc with quite a few causes and solutions as you will see from the many many posts on the subject.
Most of the solutions are inexpensive and easy so don't let it put you off mk3s.
Also see the mk3 buying guide in the mk3 section.
Differences between anniversary, colour concepts are purely cosmetic. There is no mechanical or performance differences. I.E colour concepts all have colour coded leather interiors and bbs solitude wheels and come in some exclusive colours. With nice recaro seats too.
Anniversarys have 16" bbs RX2 wheels, anniverasy checked interiors with red seat belts, red stiching on the gear gaitor and steering wheel, smoked front fog lights, golf ball gear knob and other stuff probably.
Getting a colour concept obviously gurantees leather, but the colours are not to everyones taste, although there are black ones with black leather.
Don't pay over the odds for a special edition unless it's in mint condition.
I wouldn't bother with a car without service history, golf gti's weren't exactly cheap so there are plenty around that have been looked after by people with enough cash to maintain them properly. Cars with none or with patchy service histories just raise too many questions about their past.
Leather is a fairly rare option on normal 8v and only slightly more common on 16vs so be prepared for a good hunt to find a car with leather that's worth buying.
VW do keep service records, if the car has been serviced at a main dealer. Although the records are not always complete.
Good luck with the search!
(can you tell i'm bored at work today?

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