Hi DanielReid,

From ATO guidelines, the requirements to issue an RCTI include:

1. the buyer must be approved by ATO to issue RCTIs
2. the RCTI should be issued within 28 days of making or determining the value of the purchase
3. both the buyer and seller must have a valid ABN.

Also, looking at a sample template provided by the ATO here, there is a requirement of having details of both recipient/supplier and value of taxable supplies. The solution you suggested would not have all the requirements listed there.

Since we don't offer an RCTI solution, the best practice to record this in QuickBooks Online would be to record a separate invoice for the income and expense items. 

Bonny