I always require 1st month, last month and security deposit (3x the rent total) and that weeds out a lot of the undesirable tenants. 

I am thinking of placing some security cameras in the laundry room and in the parking lot as well as motion sensor lights as the lot currently has no lights and I’d like to lessen my liability from theft, falls, undesirable people, etc.

Downtown was and remains today walkable, safe, and vastly underrated, but I’d be cautious and ensure due diligence in areas around the peripheral.

My wanting to help out some young people (the first time) resulted in police on site for domestic abuse, social services checking on child welfare, non-payments and about $2500 in damages after they finally left (holes punched into walls, damaged carpets, etc)I'm not saying don't take a chance, but make sure the rental rate is not lower than the market (which attracts undesirables at times), and do your due diligence!  

Learn about neighborhoods, how to recognize desirable/undesirable areas. 

People with an undesirable history have a higher chance of repeating again.

Is there something bad or undesirable I should know about that type of commercial property.

Add in that it is now sharing a wall to the master bedroom which is generally undesirable and my guess is that it will not add value. 

There's also a vacant lot directly across from the house that is always overgrown, collects trash and sometimes undesirable visitors.

:D im currently looking into Brooklyn, east Williamsburg, Bushwick area.... the energy that made once undesirable Williamsburg a yuppies paradise seems to be continuing deeper in Brooklyn into these areas...