I have one unit rented to three professionals; they have lived there for three years now. Two guys started the lease and later added one girl to the lease; the second year, the girl moved out and another girl moved in. After that they renewed for the third year. Now the third year is up and they will stay for another six months. So all together the lease will be three and half years.
A family sometimes can't afford higher rent, but three working professionals can easily pay for it. no kids, no pets, less wear and tear.