The rules and regulations are changing rapidly, NSW has a state legislation now
https://legislation.nsw.gov.au/view/html/inforce/current/sl-2021-0461#sec.77
Victoria has the DPU, dependable Person Unit
https://www.housing.vic.gov.au/movable-units-home-owners
and now Western Australia is getting involved
https://www.esperance.wa.gov.au/news/2022/dec/22/big-ideas-tiny-houses
I have written a series of articles that may shed some light as well https://www.cabins.com.au/blogs/news
https://www.cabins.com.au/blogs/news/how-to-make-more-money-on-your-farm-with-new-rules-from-nsw-government
Do the research, state legislation over rules councils so don’t get bullied by town planners..
Best of luck