ok, lets assume he bought the place as an investment property, then decided to move in and live there, call it home. He can elect it to be his PPOR from day one after he moved in. If he held other properties at the same time, that complicates things, but even if it was his only house this still applies. He simply needs proof, as in electricity bills, telephone etc as proof it was his residence. The rates and insurance bills do not apply, as he would have those as the owner and landlord. His address on his tax return is also a good look. He can move out of his own home, rent it out, as many times as he likes, so long as within each 6 year period, he moves back in, it will retain its CGT free status.
Some people have lived in a house for say 30 years, they move out , rent it out, and keep a PPOR at another address. In this case CGT on applies from the date they moved out and elected a different PPOR. I am happy to answer your questions if this does not fully explain the situation.
