Forced appreciation, cash out refi, infinite returns.

Just paint over it or buy some of those stick on tiles or shelf protectors.

I can evaluate some of it, but often times I don't see a spot on the wall to be patched and painted until the couch is out of the way, or a broken shelf in the fridge until all the junk has been removed. 

I used to designate shelves for each guest in my own fridge, but I got tired of cramming all my groceries onto one shelf.

If you aren't legit and don't have proper licensing and insurance there are infinite situations which could put you and your friend in a bad spot legally or even put your own personal assets in jeopardy on top of being fined for managing a rental without a license. 

I make a plastic tray out of that thicker clear non-adhesive shelf liner to protect the cabinet from leaks.  

I paint all my rentals myself and the paint is only $25 a gallon, it takes me a day to paint an entire unit so for an investment of say $50 plus supplies, I make an infinite return on that improvement.

When demand is infinite you can deal with existential philosophy and sell snake oil over and over again.That is not the case in 95% of the RE market.  

Over-index on your ceiling exhaust fan to ensure you don’t have moisture and mildew build up, particularly since that window above the bath’s inordinately undersized and has a small shelf on it that just begs tenants to store leaky shampoo bottles that leak into your walls or collect moisture from the shower. 

If true, the bills aren't getting paid however TVs and phones are flying off the shelf!