House hack multi-unit? What ROI do you target?

[Virginia Hedges]

If you are living in one of your multi-family units, and want to pay less than market rent, it will reduce your cash on cash return.  Just wondering what others consider when deciding what to contribute to the property monthly.  I also ask myself the same question when deciding how much of a mortgage down payment to make in order to reduce the monthly operating expenses. Looking forward to some great advice.  Thanks!!