Don't know any schools down there but all I can say is PAY AS YOU GO. If not you need to be VERY confident in the school, the instructors and be crystal clear of what you are paying for. Confirm hours or licence(s), a/c type, written subjects etc.
Do this for pay as you go to but you can generally change schools any time if unhappy, with a pay up front all singing all dancing deal, you may not have that option.