Primary-Residence-Only Rule
Washtenaw County imposes no primary-residence rule β Ann Arbor does. In Ann Arbor's residential (R) districts, an STR must be a principal-residence Homestay or Whole House rental owned by a permanent resident; non-principal-residence commercial STRs are generally prohibited in residential districts.
Residential-zone STRs must be the owner's principal residence
Some RestrictionsAnn Arbor City Code Ch. 97 (Short-Term Rentals)
A Principal Residence Whole House STR is a rental where the owner (or 30+ day tenant), who must be a permanent resident, does not occupy the dwelling unit while it is rented out.