Check city regulations before you look for renters

Thinking about adding some paying housemates to your household? First make sure it's legal, cautions Marilyn Bruin, associate professor with the University of Minnesota's housing studies program. Municipalities have different regulations and requirements, designed to control parking and other issues, she said.

The City of Minneapolis allows homeowners in areas zoned R1 to R3 to share their home with up to two unrelated roommates, said JoAnn Velde, deputy director of housing inspections. A couple are considered a family unit, and can have two additional roommates.

But those roommates must share the owner's household, including kitchen, Velde said. "What's important is that you can't convert to a separate dwelling unit without permits. You can't run a rooming house. And you can't put a full kitchen in your basement, create a mother-in-law apartment, and rent that as a separate unit" unless you first get a permit. In that situation, "you have to have zoning approval to support a duplex."

Some suburbs have even stricter requirements, according to Bruin. Check with your city's planning and zoning department.