Calculating a house hacking deal

[Jantsen Locke]

I am currently in the middle of negotiating a deal for a duplex that intend to live in one side while renting the other. With the combined rent from one side and my roommate I will not have a housing payment and profit $100... gross any other kind of expenses.

When using the rental calculator what is the best way to input the numbers so it takes the money I am saving currently on rent ($500) into consideration?