The Blackstone Group, according to industry sources, has amassed a war chest of roughly $250 million to buy non-agency, nonprime mortgages, another sign that “big money” investors have returned to the sector. At this point, it’s hard to say how much origination volume in the sector will grow. It’s well known that over the past 18 months, bond insurance giant PIMCO has been buying loans that don’t meet the qualified mortgage test from Citadel Servicing and others. The reason is ...