duplex analysis inquiry

[Nakia Addison]

I would like clarification when analyzing a duplex with the option of house hacking. For instance I rent out one unit and I live in the other. Questions are listed below:

Q1: When I use the calculator to input the monthly rent, do I only account for the unit that is being rented out, or do I account for my unit as well even thou I will be living there?

Q2: The ultimate goal is to live for free with using the house hacking concept. However; if one unit covers the mortgage only, than my expenses would be my own utilities in my unit? Is this correct?  

I may be overthinking but I would like clarity. Thank you!