Social Finance, a nonbank that has focused on refinancing student loans, launched a jumbo mortgage lending program this week. The lender is offering loans with downpayments as low as 10 percent and balances as high as $3.0 million with no requirement for private mortgage insurance. SoFi is offering 30-year fixed-rate mortgages and adjustable-rate mortgages, including a 5/5/20 ARM with a 10-year interest-only period. SoFi said it is looking to originate ... [Includes one brief]