Somewhere between R250-400/hr for a professional teacher w/qualifications (E.g Jazz Workshop is R199/30m). At a certain level it's worth it, this level of teacher is gigging regularly, has contacts throughout music and those alone are worth it...at a certain skill level.
There's a goodly amount of peeps offering beginner lessons, I've bumped into a few of them...my first question is where they learned from. It's usually the only question, because the answer is generally 'youtube' and then we move on. ?
If you pop into Mars (Tableview), chat to Josh (salesperson) and ask if he is still doing private lessons - he's a really good rock/metal player. Though he's younger , he has taught at a good few schools around Cpt. Oh and you'll get to perv some Epi's n Gibson's as well.