Offer your thoughts or opinion on the input financial query or topic using your financial background.

Question about MBS and how it pays
A Mortgage Backed Security or MBS is the security.  It's not an entity, it's essentially a contract.  As an investment they function more or less the same way a bond does. There is nothing wrong with the concept behind a Mortgage Backed Security.  Functionally securities like these allows banks and other institutions to lend to high-risk borrowers.  You package small slices of a wide range of risk from a large number of mortgages and the investor sill receive something similar to the average of the rates being charged.  Essentially from a big pool of mortgages of varying risk you will create a different big pool of bonds that can be sold to investors based on some sort of expected return.  For a frame of reference on a much smaller scale look at peer to peer lending sites like LendingClub and Prosper.  The idea is lots of people of varying risk profiles make requests for loans of varying amounts.  You bring your $2,500 and invest $25 in to 100 different loans.  This way even if a few default you will still eek out a profit.  It also allows you to include riskier borrowers without materially impacting your expected return.