More than two dozen trade groups signed an open letter to the administration and Congress urging them to preserve what works in the current housing-finance system and get more private capital back into the market. “There is a pressing need to ensure that the existing progress is cemented rather than cast aside,” said the groups, which include the Mortgage Bankers Association, the Community Home Lenders Association, the Community Mortgage Lenders of America, Independent Bankers of America and the Credit Union National Association. The groups want to make sure that any effort to change the role the GSEs play doesn’t result in market disruptions that reduce access to credit in the single-family and multifamily space.