Install some kind of energy meter inside the main panel and track the usage for the circuit the hallway lights are on and just pay that usage and put the meter back in the tenants name.Figure out what is driving up costs and do an improvement program to drive those monthly bills down, caulking, insulation, more efficient heater etc. 

If I were in your shoes, I'd stick the cash in a high yield checking or savings account (or Bitcoin*) Then, once you pass the bar and figure out where you'll be for the upcoming chapter use that cash to fund the most investment-efficient purchase you possibly can, like a legal 4-plex in Holladay, a Triplex in Sugarhouse, or the NV equivalent. 

I am quickly going beyond the limits of what I can manage with spreadsheets and think utilizing a database structure will enable me to become more efficient.  

Would it be better to buy a fixer upper in the next great location during a buyer's market and do a spectacular (and cost-efficient) renovation?

I am new to real estate and I am seeking aid In specific looking to learn the most efficient way to locate properties, structure the deal with an investor, have a reliable lawyer and appraiser to ensure accuracy and efficiency.  

@Daniel Saunders just a word of caution as it relates to 3rd party management; we have found that this solution only tends to work well if you have a park that is already stabilized and running at or close to efficiency. 

Especially in NE, E and SE Austin due to the proximity to the airport, toll road and the new Tesla factory.

A VERY big factor is going to be Property Management team, having a great PM agency in place to assure good tenants.

@Bruce Lynn That makes sense about the control factor. I

The big guys, Home Depot, Lowes, Best Buy,   never stock anything & totally depend on direct factory shipments.