I go to service a rental , landlord called because tenant had no heat .

Hi Joseph, I'm an electrician in MA, I'm 99% sure that the building code states (in NH) that each unit must be interconnected to one another, common practice would be to install a heat detector in each unit and also in any common hallways or basements.

The 3 bed unit pays it's own utilities while the 1 and 2 bed apartments pay their own electric and cooking gas but owner pays the heat.  

And the heat was one of those gas wall furnaces which only heated the living room.

The whole house is electric, electric hot water heaters, baseboard heating, etc.

Free time isn't something I have and the condo are cheap and they rent well because they come with heat and hot water. 1 bed rents for 1050 and 2 bed for 1250.

Here is how I view the numbers:Mortgage Rate 5.00%Length of Mortgage in years 30Monthly Mortgage payment $1,503.10 Taxes $400.00 Sewer and Water $100.00 Trash $- Heat/Utilities $- HOA $- Cap Ex and Ops $175.00 Insurance $166.67 Mgmt Fee $370.00 Vacancy $296.00 Total Expenses $3,010.77 Unit 1 $2,200.00 Unit 2 $1,500.00Total Revenue $3,700.00 Cashflow/month $689.23Cash on Cash Return 11.18%

the cost of the appliances and the a/c and heat repairs should have already been added in the price of the rent.

Because I'm an idiot, I thought I would save some money by shutting the heat off in the other unit of my property (I live in Denver and it was bitterly cold this particular week).  

I also recommend you have them wash and dry anything cloth on a high heat setting.