I didn't approach them until I made offer.PURCHASED: 200KTERM: CASHRENOV: 70K of 100K (New roof, windows, new 2 apt, new 2 commercial, new gas forced air furnace X 3) RENT: 500+550+700= 1750/mo (700 can be 900-100 if I renovate and kick tenant out in future, old rents 400, rents in 1 day)           1500+1200= 2700 (commercial)GOI: 4,450/mo or 53,400 annually ( I get late rents, because inherited tenant lost job, but we good now)Tax : 7,000Ins: 4,000Utilities: paid by tenantNOI: 42,400 or ROI 14%, 42,400/300K this is my inlaw's 200K from #2, and our 70K.

Natural gas, or electric heatpump with gas, is the most popular, if you already have gas to the house.Natural gas is the only utility I pay for that has gotten cheaper over the past 3 to 5 years. 

If I were you, I'd install a high-efficiency gas furnace(they can reach the mid-90% range for efficiency.)

*Gas money 

One property was a mobile home park were I tracked rent payments as well as natural gas usage and payments.

The barber, the gas station, the nail salon and the sandwich shop all move to the new strip center down the road in hopes of a higher return.  

The "gas and electric tenant" is used to describe what the current owner is paying for tenant utilities (not common areas). 

Tenants pay all electric, gas, water, and trash.

The house was winterized so gas and water was off.

.$2,000 New furnace after finding the heat exchanger was cracked$1,200 handyman labor to paint exterior window and trim, haul debris from yard, replace counter, get shower tile back to watertight, fix ceiling damage from water$600 materials, including paint, kitchen counter, locks$600 new vinyl kitchen floor$200 three yards of dirt to correct grading around the foundation$200 plumber to replace gas valve, fix leaky drain, replace p traps in kitchen and address a couple other concerns I had$37,050 all in.I spent about 30 hours of my own time buying materials, stopping by to manage workers, and doing some minor work myself.