Industry trade groups this week stepped up their efforts to block the imposition of additional fees on Fannie Mae and Freddie Mac MBS as a way for the government to pay for an extension of the payroll tax holiday and unemployment benefits. Late this week, the House-Senate conference committee announced it reached an agreement on a $150 billion extension through the end of 2012, although final details of the deal were not yet finalized as Inside MBS & ABS went to press. Lawmakers had been considering raising $4 billion of new revenue from increased guarantee fees from the two government-sponsored...