To make a roommate arrangement work, “it has to be handled like any other business transaction,” says Sylvia Bergthold, who wrote a book on the subject. She and other experts recommend:

– Run a credit check on prospective roommates. Bergthold recommends a company called citicredit.net, which charges $9.95 for a tenant credit report; a number of other companies also do this for about the same amount. Some experts also recommend asking to see the last several pay stubs and a copy of the driver’s license, to verify the roommate’s income and identity.

– Ask the prospective roommate to co-sign the lease.

– Agree on how utility bills are to be split. Some people recommend that every roommate just use his or her own cell phone, and don’t bother with a land line for the apartment. This way you don’t have to worry about splitting phone bills.

– Ask for references, and check them.

– Ask prospective roommates why they are moving, how many times they have moved in the last five years, how long have they have been working at their present job and how many jobs they have had in the last five years.

– Talk honestly about all sorts of lifestyle issues: What time do you go to sleep on weeknights and weekends? How neat are you? Will you bring home dates (or one-night stands) for sleepovers? Do you smoke? Do you drink or use drugs? Do you have pets? Only you know which of these behaviors is a deal-breaker for you.

– Agree on house rules about guests, quiet hours, smoking, cleaning and other chores, whether to share food and household supplies, etc.