An LLC is useful for two things: anonymity and legal protection.

A quiet title action is a legal action against anyone or entity that has an interest in the zombie property.

Wishing you the best in your self-management journey, but remember, a good property manager can still be invaluable, especially if you’re not familiar with the legalities of property management.

I personally have $100 cash ready to buy your property right now.Second, no, the open ended listing agreement suggested by some on here is not appropriate because that would mean that you think that the agent is actually representing you - dual representation - which is not beneficial to you and should not be legal, in my opinion.  

This comes with some other ramifications around legal liability and the ability to get a mortgage on the property.The other way to fix this is to create an LLC now, and both you and your MIL contribute the current properties into the LLC, then the LLC 1031 exchanges the old properties into the new property.

Maybe this would also make it worthwhile to jump through the city hoops to make the basement a legal unit.Then you could maybe put a LTR in the basement who could assist with the STR in the main area.

But if you both want to own/control the properties it probably makes more sense to have a legal entity.

I am renovating a walk out single family home to have a separate legal unit in the walk-out basement. 

The application is not a binding legal document. 

Most legal disputes are over security deposits and for small amounts.