In practice unfortunately most attempts seem to get aborted as zoning requirements differ too much to be economical. For one the plumbing tends to come with per resident requirements for the units they wish to sell for health code reasons of wanting a shower, toliet, and bath.

Going more "dorm" style could work for low end if there wasn't a pandemic and even then it would carry plenty of risks that would scare people away from such an arrangement let alone the consumer desires.