I had a 205 GTI back in 1991, huge fun and quite quick in its day but an absolute bag of crap in the reliability stakes. I sold it to a guy who had an even bigger bag of crap XR2 that smoked like a shot down Messerschmitt in a 1970’s war film.
The 205 GTI followed a hideously unreliable and heavily tuned mk1 GTI so was at least an improvement on that in all areas except solidity of construction.
A string of old man’s mk2 GTIs followed when I was in my 20’s and they were all built like tanks and never put a foot wrong in the reliability stakes. Maybe old men know a thing or two?
In fact back then there was a big following of old man’s mk2 GTIs from young guys, with GTI International seeing 10000 visitors some years, Worthersee even more again.
Is a mk7 GTI an old man’s car? Being as I’m old now and like them then maybe they are

In fact I wonder what I’d drive if I was young now?
As Yusee says, just buy on condition.
GTI’s don’t need to be loaded with options, old men’s cars are for creature comforts and golf trollies, GTIs should be kept fairly simple.
An older GTI on a 12k budget loaded with options is just begging for stuff to start going wrong.
Forget options, forget colour, buy the best condition car you can find and it should look after you and your wallet.