Sometimes before even asking a specific question, they will start rambling a rehearsed excuse story on their credit, previous landlord troubles, job losses, etc.

They may be family/friends but it is still business and having your t's crossed and i's dotted will save you trouble down the road. 

Add 1 interior door to bedroomI.Remove 1 interior door in master bath but keep openJ.Build 1 15 ft fence (exterior)K.Build 1 45 ft fenceL.Fix floor-grade garage additionLooking for rough estimate at this point.Thank you!

While there is a lot missing, even your market rents of $550 and $750 scream trouble.  

Had the cops come about 12 times... then had the stormdoor guy build a fence and post no trespassing, so they went somewhere else.11. 

Additionally, you might want to install a fence with a self-locking gate and make sure all pool equipment is up to code.

sell the ones that give you the most trouble, and roll the money into the others.

You said two things that are extremely troubling - "I want to scale" and "HML".

He’s going to be more trouble in the future.

At minimum, look at the assessor's site on the lot lines but ideally, have it surveyed so you know what you will own (esp if you are going to build a fence or structure).Tons of lessons, always learning, looking forward to reading what others want to share here!