Redwood Trust is preparing to issue a $343.28 million jumbo mortgage-backed security, according to a presale report by Kroll Bond Rating Agency. Sequoia Mortgage Trust 2017-1 will include mortgages from 132 lenders, led by Quicken Loans with a 7.8 percent share. Servicing for loans in the MBS will mostly be handled by Shellpoint Mortgage Servicing. Redwood will retain 1.0 percent of the dollar volume of the MBS, according to KBRA. Three firms ... [Includes two briefs]