The Phoenix area could save millions of dollars by housing people with mental illnesses instead of allowing them to become homeless, a new report finds. AZCentral reports on the study, from Arizona State University’s Morrison Institute of Public Policy, which found that it is 30% cheaper to provide housing with on-site behavioral and medical supports, than to allow a person to become homeless. A person’s healthcare costs decreased on average by $20,000 once placed in this type of supportive housing, the study said. AZCentral spoke to an emergency room doctor who, over his 40-year career, has treated a number of people in crisis who were dropped off by police.