Everything is supplied by the army, including rations, uniform (including boots). However, there is a fee of around $60 per year and $10 for camps to cover accommodation and CPR courses (if applicable).
I'm in army cadets you don't have to pay for uniforms all you have to pay is camps and weekly fees which $4.00 here you get paid to go to summer camp =)
Yes you do have to return your uniform when you leave the ACF, as your payment when you started was simply for the 'hire' of the uniform. If you do not return your kit when you leave you will receive...