As others have pointed out, mixed-use is a bit touchy right now for many lenders, so if any one element, no matter how small it may seem, doesn't line up, they will pass.  

If the cash flow on the existing properties goes close to breakeven, seems like you would be increasing your risk of large capital expenditures, like roofs or heat pumps, without cash flow to sustain them. 

So even elements that don’t appear damaged can be contaminated.

Do energy efficient upgrade tax credits (for new windows, doors, heat pump, etc) work for rental properties? 

You are also in the northeast which is crazy expensive to heat, especially if using electric heat.

Tenants used the propane for 9 years, then we decided to switch to heat pump with central air and stopped using the propane.

. $225KProperty Features:First floor: 2 bed/1 bath, potential rent $1,200Second & third floor: 4 bed/2 bath, potential rent $1,500Separate utilities and heating/central AC systemsInitially, I projected over an 8% cash-on-cash return.

It's mainly used for heating and the fireplace.

Take into account elements like diversity, tax advantages, cash flow, and potential for appreciation.Determine Your Risk Tolerance: Investing in real estate entails some risks, such as shifting market conditions, vacant properties, and unforeseen costs.

Running the heat is not nearly as costly as flood damage.You winterize by (at minimum) keeping heat on and draining exterior and unnecessary plumbing.