Family members include parents, children, siblings. IP is negative geared.
From ATO perspective: Tenants pay rent, landlord pays tax on the rent. I reckon there is no tax avoidance or tax evasion?
From Centrelink perspective: Can tenants claim rental assistance? Does the tenant and landlord's relationship affect the claim? Do they need to disclose the relationship? What if the landlord is paying the tenant child support?
From bank's perspective: Can the landlord use the rent as an income to fund the mortgage, esp. when the landlord is supporting the tenant (aged parents, ex partner) financially?
Another question may be irrelevant: Do children have legal obligations to take adequate care of aged parents in Australia? Is it considered immoral to lease to parents and charge rent?
This is above my pay grade…