From tax stand point I would think you can separate from primary and be okay with IRS being that IRS will not be local code enforcement.  

@Edgar Duarte Selling now under the primary residence exclusion avoids capital gains taxes, allowing you to reinvest the $500K equity in diversified assets like index funds or additional rental properties.

In my area this is the primary permit that is required that is virtually never got. 

This is an investment property of the seller, not their primary residence.

In most cases, I don't recommend renting out your primary residence especially if you have no rental experience and that is because usually your primary residence was bought without the idea of renting it out.  

At minimum, stage the living room and primary bedroom to give it some warmth.That said, have you thought about cutting bait and putting your money into a market where the numbers actually work?

I would rent out my primary and end up making more than I spend living in Australia.

Since there is a co-owner, you would have to purchase the property and it is really hard (if not impossible) to pull a HELOC as the basis for the purchase (since it is not your primary residence). 

Will you be keeping or selling your current primary?

If that leads to a more structured and education based meeting, then that is great - if it remains just a place to gather and bounce ideas and network, that's great too.