B2N2 - To make it a condition of maintaining approval to allow only a certain percentage (say up to 25%) of the full course cost to be on deposit with the ATO at any time.
IMHO, it would be fairly straight forward to include an 'audit' of student account balances picked at random by the inspectors who 'audit' at random student training records for compliance as part of their function.
Such information would not be commercially sensitive from the standpoint of profit or loss, just a simple tabulation in the file provided by the school and signed by the student which can be kept on a simple spreadsheet throughout the training....
DateXXXX
1. Total Course Cost......
2. Total Course Balance Remaining....
2. Total Student Account Balance.....
I don't believe any ATO needs a bigger percentage at any one time on deposit to fund the training.