If the economy worsens, Fannie and Freddie could end up costing taxpayers well over twice the $150 billion they have already cost:
The Federal Housing Finance Agency, which has regulated the former government-sponsored enterprises since they were seized during the financial crisis in 2008, said the figure was based on the worst of three scenarios for the economy and housing market that assumes a “deeper second recession.”
Under the best-case scenario, which would be a “stronger near-term recovery” in housing prices, the bailouts of Fannie and Freddie would reach $221 billion. The third scenario, in which housing prices continue on their current projections, would result in the combined bailouts reaching $238 billion.
Keep in mind that the administration’s current and future deficit projections do not account for the estimated cost of covering Fannie and Freddie’s losses, even though the CBO says they should. So whatever number for this year’s deficit you see in the news ($1.3 trillion last time I checked), you can mentally add around $200 to $300 billion.