Just sounds like you bought a shitter tbh. I did the same thing, bought a 160k one with no recent history and she was great, then bought low-miler with full pug service history and had nothing but problems. It happens. 
EDIT: And as a recent buyer of a tidy 205 i'll tell you now it's a different league to look after, and not in a good way.
EDIT: And as a recent buyer of a tidy 205 i'll tell you now it's a different league to look after, and not in a good way.