The purposes of this subchapter are—
(3) to provide participating jurisdictions, on a coordinated basis, with the various forms of Federal housing assistance, including capital investment, mortgage insurance, rental assistance, and other Federal assistance, needed—
to expand the supply of decent, safe, sanitary, and affordable housing;
to develop and refine, on an ongoing basis, a selection of model programs incorporating the most effective methods for providing decent, safe, sanitary, and affordable housing, and accelerate the application of such methods where appropriate throughout the United States to achieve the prudent and efficient use of funds made available under this subchapter;
to provide credit enhancement for affordable housing by utilizing the capacities of existing agencies and mortgage finance institutions when most efficient and supplementing their activities when appropriate; and
to assist very low-income and low-income families to obtain the skills and knowledge necessary to become responsible homeowners and tenants.