The Canada Mortgage and Housing Corporation insures $480 billion in mortgages. Some have compared it to Fannie Mae and Freddie Mac in the U.S. So, how exactly does the CMHC work? BNN speaks to Ian Lee, director, MBA Program, Sprott School of Business, Carleton University, Tsur Somerville, director, Centre for Urban Economics & Real Estate, University of British Columbia, and Larry Smith, professor emeritus, University of Toronto.