Give him a written notice that it's unacceptable behavior, particularly when you have women and children in the area, and that another instance will result in termination.

for example, I was told that that famous Rich Dad, Poor Dad (whatever) book starts off with the author explaining that some relative passed away and left him $1mil. 

Sounds like a famous "House Hack" type of situation.

For instance, there are a few well known institutional lenders here in town who have horrible reputations centered around not getting loans closed, having poor appraisals or unreasonable underwriter guidelines...it doesn't matter how good a rate or fee is if nobody in town wants to work with them!

For instance, one of the bedrooms has a sagging floor due to a few floor joist needing to be replaced and their bathroom needs the same thing.

This will not affect the amount the tenant pays, because the tenant's payment for rent plus utilities is 30% (40% in some instances) of their income, no matter what the rent amount is.I wish this was in my market. 

For instance, one of the bedrooms has a sagging floor due to a few floor joist needing to be replaced and their bathroom needs the same thing.

For instance YouPorter support is awful but the product normally works well for me.

I can’t imagine a world where a landlord is so greedy that they would charge friends if their tenants rent for the short term, especially if there is no lease or paperwork that outlines any terms or conditions regarding instances like this.

Quite frankly if its a neighborhood that is so unstable that some blocks are investable and others are not than its not a neighborhood I want to be in anyway (and there are plenty of them, don't get me wrong).For instance, I would invest anywhere in the Hamilton neighborhood.