For most medical services, the govt will reimburse you a set rate. The GP or specialist can charge you whatever, sometimes the same as the govt reimbursement, sometimes quite a lot extra. You don’t pay anything at public hospitals (which are nice).
I recently had some great problems, I stayed overnight in hospital twice, for a total of 3 nights in private rooms, had an internal scaffold inserted in my artery. i also had numerous consults with specialists and drs.
The whole thing cost me about $500, a few days work on average wage.