The system varies from state to state. In Victoria all pension card and health care concession card holders recieve free treatment and transport. There is also a subscription scheme which provides 100% coverage for emergency treatment / transport (including air wing) and authorised non emerg transport. For everyone else it is around $300 for ambulance attendance, and a minimum of $700 for transport. As you can imagine AME and rotary transport isa bit more exspensive.