The heat was very high recently and the air conditioner above unit had some issue and the water dipped from the pipe of that unit and damaged my unit.So I requested clarification to my property management company how they provided a quote without identifying the root cause, but haven't got any response yet.

We replaced a toilet and have repaired/replaced components of both heating units.

Can you make all electric with mini-splits or other individual heating systems?

Severely Under performing duplex for sale with all owner paid heat / single boiler.

This is the simplest method, but it also means your tenants are more likely to abuse the utilities by leaving windows open with the heat or A/C running, leaving lights on, ignoring the toilet that constantly flushes on its own, etc.3.

The house is newly renovated with central air and heat, all new appliances, and granite countertops.

Depends on size, brand, type (electric, gas, electric heat pump style).I just replaced my gas one at rental and I went with the 12yr rated one and bought the Allstate protection plan for $69 that gives me 5 more years after the 12 yr manufactures warranty. 

I've seen them written where the Tenant handles all maintenance except for the structure, which means they cover heating, plumbing, electrical, flooring, ceiling, doors, and windows.

Many have boiler heat and A/C wall units.

As long as it's "heated sq footage" it's as easy as calling the property appraiser and getting the sq footage added to public records.