I have not seen a decrease in demand for my multifamily rentals here in Columbus, Ohio

You actually DECREASE your Debt/Income. 

.- projects to decrease costs.  

From year 2 onward, the ROI further decreases, seeing as the yearly nominal gain is still €9000, whereas the net equity increases.I apologize if this was a bit extensive, I was partly writing this to recap some thoughts for myself :) If anyone has come across similar markets and/or knows of ways to handle this, any input is highly appreciated!

If it is an A class rent area, you can look at decreasing.

There's not much I could do to decrease the expenses other than homesteading the property and decreasing property tax by about $1500/year (new payment would be $1050).There's what I know that I could do to increase profitability 1. 

I have good luck with the regional office here in Nac. 

I can tell you that the learning curve will exponentially decrease from deal one to deal two.

I am investigating if it would be advantageous for us to reduce our tax liability (decrease profits).

Pay off one of the mortgages which would then increase their cashflow and decrease their expenses meaning they need less reserves.