Glamourcide, i actually work in an Australian Apprenticeships Centre
Not sure how it works over there in QLD but I'll give you the WA speel anyway XD

First, you don't need any other qualifications to study for a trade. Most of the younger kids that are going work experience are doing it mostly to get their foot in the door in the hopes that the employer they're doing the work experience with will put them on as an apprentice.

Over here it isn't possible to become a hairdresser without doing an apprenticeship. To become a qualifed tradesperson you need to complete a certain amount of years of on the job training along with TAFE units to be fully qualified. Hairdressing (over here) has a 36 month term (3 years). Usually that's made up of attanding tafe once a week for the 1st 2 years of your apprenticeship or doing a block - so attending TAFE once a year but for 3 straight weeks for example while you're working on the job and gaining every day practical experience. It is also a requirement that you are supervised by a senior/fully qualified trades person at all times so you can learn from them while you're doing your on the job stuff - and to make sure you don't turn anyones hair green

Cert III means that you are a fully qualified trades person.

The beauty of an apprenticeship though is that you'll be saving 10K, you'll also be getting paid to study for your dream job & if you're really lucky your employer may pay for your training. Employers here will do alot of an apprentice that are willing to put their back into it.

As for beauty therapy there are traineeships that you can do with an employer that are possible to do part-time, but instead of taking say 12 month they're take 18. There are only at a certificate 1 or 2 level though.

I think your best bet would be to call your local TAFE and ask them for the number of an Australian Apprenticeship Centre over there so you can suss out how everything works. I am pretty sure that MEGT Australia is an AAC over there, but not 100%!

ETA, just thought I'd add also that the goverment over here has little "perks" for apprentices to help them along their way. Apprentice Hairdresses are entitled to a Wage Top Up, which is Direct Debited into their bank account every 6 months for the first 2 years of the apprenticeship. It's a $500 payment. There is also another $500 payment called the Trade Scholarship that you get at the end of your first and second year. You are also entitled to a payment to cover for "tools" as well - this usually came as a voucher to spend at specified suppliers but you now get it as cash since the gov as changed it around (which imo isn't good because instead of buying tools most kids are going to flog it on a weekend out!) it's probably not much, especially when you have your own little brood but it would def help to be put towards day care etc.