When I was in the used bike trade I found 125s a big source of frustration:
Almost daily I’d be asked if I had a cheap one.
95% of them have been trashed in the first three years by 17 year old owners.
Whenever I did get a decent one I’d have to put up with a succession of prospective ‘buyers’ expecting me to let them have it for a couple of weeks pocket money.
Pass your test and look for a 250, there’s still plenty of grey import trailies out there (I imported 250 or so of them) that have had considerate, mature owners. You’ll get a better bike that you’ll be far more likely to want to keep.