As Winston I think uni is well worth it. Even for Arts students, b/c if you just want to do a job that isn't really specific. Ie., not IT, not Architecture, not medical, not law, not accounting. An arts degree still gives you some "ground" to apply for jobs. Thou you could argue that and I know people who just went to work in a bank after high school and after 5 or so years they are doing the same work as some uni grads without the loan but they might not have the unique (I think) uni life.
I've lived at home and away from home.
At home:
Fees that is $15k for the 3yrs.
Course related costs: $3k for the 3yrs.
You get the allowance or the weekly loan. $170 per week.
Most students draw out the max. If you have extra you can keep in the bank or save up for something else.
Some of the costs could be covered above with the course related costs but I'll list them all up:
Weekly IME or those around me:
$30-40 for bus.
Maybe $50 for lunches either buy or make it.
Entertainments maybe $50-100. This varies a lot, ie., cafe lunches or the odd dinner with friends outside etc ... a normal meal could be $18-25 without drinks. And how much pubs/pizzas.
Your internet and mobile phone

Buying clothes, socks, underwear as required
Haircuts
Various gifts for Christmas/birthdays/valentines/mothers-fathers day etc.
Own hobbies of your own.
Maybe trips away at the occasional weekend.
Bookmarks