I was half teasing you. But you should tell the bank the truth. If it is going to be a rental long term then you may be justified in telling them this even if you do intend to live in it in the short term.
What you tell the OSR and what you tell the bank doesn't have to be the same either...
Banks don't mind if you commit fraud as long as you keep paying.
For the answer to the duty question have a look at the duties act (QLD). Then have a look at the Crimes Act (QLD) and search for financial advantage by deception.
