You need to focus on what hurts the neighborhood and will cause your property to fail to attract new residents or retain the old. 

The son thinks his mother has the right to retain everything in the barbershop since the tenant owes his mother over $6k in back rent.

I always retain keys to our commercial buildings.

So all things considered, do you want to retain the tenant, or keep her?

When it comes to deciding on the organisation of your business a lot will depend on your goals; whether you wish to retain the earnings in the U.S.A. or have them repatriated; and your present situation at home (salary, other income).  

It will cash flow negative, but not too bad and I still retain ownership of the property.What else am I not thinking of?

You can obtain a "sub-servicer" as your back room to grow and retain selected notes for servicing if you like.

My experience is that each title company, if not onwed by an attorney, has an attorney on retainer for title issues they can work through when needed.

Do you retain part of the basement for common laundry (if each unit does not already have laundry)?  

I’ve read that banks won’t provide a loan if a property is in an LLC.Would you recommend my partner and I retain the land trust or create an LLC?