Our personal one stopped heating a good amount of water so I ended up with new thermostats and replaced the bottom element for under $50 and thats with a good element.

And while i haven't seen it reflected in the monthly reports, from helping some house hacking clients and some other first-time buyers in Denver lately, I can feel the market heating up -- more homes going in the first weekend, more going for over asking, more multiple offer situation. if you're breaking even, then great.

It could also be the age of the systems (roof, electric, plumbing, heating) or other factors. 

The nice part is, I renovated the whole thing in 2020(new shingle roof, new siding, new heating system, new HW tank, new kitchen, etc.) so I dont foresee any big CapEx expenses in the near future.

The heat pipes will freeze and burst if the heat is not left on. 

Is the current tank shot or just the heating elements?  

Fifth, elements outside your planning or control can increase expenses significantly; tax increases due to budgetary shortfalls, insurance costs doubling due to natural disasters, tenant damage beyond what the security deposit will cover.  

Like plumbing and heating.  

Your renovation number seems very low for a newbie trying to get this done in Ontario: you'll have to split the single-family and then also put in another kitchen and bathroom, manage the heating somehow and then gas and water.

It pays the taxes, the water and sewer, and the cost to heat the property while leaving some for maintenance.