Excessive candle burning.....

I take an honest look at what the building can support, give an extra margin of safety, and take out about that much. 

Addressing the problems is like trying to put out small individual fires in a forest that is burning.

I would update your lease to include fines after an initial warning about leaving trash or personal items in the common space.I wouldn't allow tenants to mail in the rent.I allow them to deposit directly into my account, ACH or Zelle.Maybe get extra trash cans so that they don't have to leave their bagged trash by a full can.

@Ryan McGrath I think your first concern is to make sure it's a legal rooming house or to understand the steps that it will take to make it one - which I'll bet would include things like extra egresses and a sprinkler system.One incident / phone call / police visit where word gets back to the building inspector and you might find a big red "VIOLATION" sticker on your front door.Next, I'd want to do some forensic accounting. 

Anyway the week i was closing on my property the neighbors placed burned up.

It took 1 year to get all of the offices and the 7 extra parking spaces leased out, but now it cash flows beautifully. 

(This single thing cost us about $6K extra in revenue. )  ARV was $160K. 

I had heard countless stories about how some burned out mom and pop ran their properties into the ground and then sold for a huge discount to another investor who made a huge profit. 

My back-of-napkin math so far seems to suggest that going for the bigger unit won't necessarily bring in a lot of extra rent, but could add a lot of value when I sell it, so I'd be absorbing a lot of extra taxes for the time I own the property.Any thoughts or insights would be appreciated,Michael