The era of increasingly cheap money that fueled the housing recovery and record home-lending profits is showing signs of ending in the mortgage bond market.

Fannie Mae-guaranteed 3 percent securities, which lenders use to price new loans, tumbled last week to the lowest since Sept. 12, the day before the Federal Reserve announced plans to add $40 billion of mortgage debt to its balance sheet each month. The drop, as lawmakers struck a budget deal and the central bank signaled it may conclude the open-ended bond-buying program this year, could lead to further increases in homeowner borrowing costs from the record lows set in December.