If your willing to do so, you can live in the casita and then rent out the main home and have your tenant pay the majority/all of the mortgage (depending on what type of deal you find obviously). 

As a fellow West Aussie who's now living in the US, I can tell you this forum and most of the training/courses you'll see online regarding multifamily investment isn't relevant/applicable in Australia.

Currently, I live in Utah.

Less government workers will live in DC.Any upsurge in listings for sale or rental will be taken up.  

(this is always what I make sure to do with all of my clients)With an FHA loan, it means you would have to owner occupy and live in Columbus Ohio.

I live in CA and own my primary residence. 

I intend to get a single family residence, add an ADU, live myself in the residence and rent out the ADU as a studio apartment long term.I have checked my city's ADU laws and long term renting is permitted.Question : can I obtain the REP status while maintaining the ADU while it is in my primary residence?

You should vet the company to ensure they have the resources to pay the rent.You ALWAYS do background checks on the people living in your property because if you let in an axe murderer and they harm someone, you are likely to get sued.Whether or not you charge an application fee is up to you.  

(Instead of a real estate portfolio of 9 rentals, I have the experience of living in 9 rentals...)

Quote from @Cooper Schmidt: Hello Everyone,I currently live in Abilene, TX and serve as the Director of Basketball Operations at Abilene Christian University.