While interviewing more than 60 ADU Homeowners for the ADU Case Studies project, I came across several different ways that people use their ADUs. I heard time and time again that ADUs provide housing flexibility and give their owners additional rental options as their life circumstances change. ADU owners can Rent One, Both, or Neither. But I’d always assumed that when an owner decided to rent out either their house or ADU they’d be renting it to a single household. Then I got to talking to Lisa Lonstron who lives in her basement ADU. Her other house – the one she lived in before she turned her basement into her apartment – is a rooming house.