Standard accounting does not do it that way, you do not enter expense and income in the same account.

You enter the expenses, and you enter total sales income

on the P&L income is reduced by expense to get net taxable profit

I am not sure if the Australian version has billable expenses, […]

Resolution for 'count against the customer issue: 'how do I enter a transaction without using an invoice and adding a chart of account' available: Yes.

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