New Electric Busses.

Where I lack understanding is at what point do you start making money for example you buy a duplex lets say it was 300k the monthly mortgage is 2,500 each renter pays 1,500 thatd 500 cash flow which is I guess “profit “ but as the landlord you're responsible for major repairs such as but not limited to roofs, plumbing issues, electrical issues that all can be expensive you would have to have money saved so that 500 cash flow is profit but wouldnt it just have to sit in a bank account? 

I assume the humidity is coming from heating water and it doesn’t matter if that heat is gas or electric stove.

There also should be very few (if any) piping or electrical penetrations through the fire wall, so I don't think your rodents are getting in that way. 

The doors windows appliances flooring ventilation hot water trim along with electrical wiring What was the outcome?

Electric heat is outrageous and no one would install it.

Well here I am going on 55 year old and been in the electrical wholesale business for about 34 years now.

I currently pay the water and internet bill out of pocket and only request rent and the electric bill be paid for by the tenants.

Dates of updates to the Roof, Electrical, Plumbing, and Heating systems4.

Door replacement and framing (lack there of) and poorly installed electrical from the previous owner.