Certification of Income Affordability and Housing Size Declaration of Eligibility  for the District of Columbia’s Inclusionary Zoning Program.  MHCDO provides consulting services to conduct the mandated process certifying of prospective IZ tenants for property owners, property managers, and developers.For further information about how MHCDO’s IZ Certification services, please contact us by emailing  or calling 202-396-1200.Please click here for more information regarding the IZ Certification process for developers and property owners.