If you are getting a long term rental, you may have some upfront work, and then whenever a tenant move in / out have some work, but typically for long term rentals you aren't touching / doing things to it every day. 

Kinda hard to tell when someone leaves if they're always on the road anyway (I think I saw him once after they started renting) and I can't be there everyday to monitor the situation and they don't tell me otherwise.

Take a look at BP's blog where new articles are published every day: https://www.biggerpockets.com/blog4.

They generally have large portfolios allowing for in house maintenance and management staff along with a point person who is communicating with the local housing authority on a regular basis and has the ability to streamline operations. 

The money being borrowed from the bank is "every day people's" money.

So, I know this is getting a bit off topic, but regardless of basis per unit, I simply don't see a property with $37k NOI today nearly doubling NOI when the incomes are that low for the area.  

I lived in Superior for a while and commuted downtown every day (get satellite radio ha).I'm a realtor, so fortunately I have instant access to what is hitting the market and it's still very hard to find something before 50 other people have found it as soon as it hits the MLS.

I think as someone who does new construction every day this is all things they would agree with.

Is anyone aware of a good data sheet that provides some basis for OpEx?

We debated selling the rental to pay off our primary mortgage, our basis is at least $1.1m on the rental property.