While one bank might have only a couple of loan programs available to the consumer, a mortgage banker is a licensed professional who offers a wider variety of rates and mortgage terms for you by accessing a network of lenders that includes major banks, credit unions and finance companies. Furthermore, a mortgage banker is not beholden to any certain bank or lender, hence, there are no special interests involved to use specific companies. In essence, a mortgage banker “shops” loans for you.
Also, loan rates can rise quickly. Many people try to “shop” for loans with various banks and lenders, but because rates can change daily or even hourly, you would have to be getting a current quote simultaneously from every lender you’re shopping with. (And unless you lock your loan with that lender immediately, the price of the loan could change at any moment.) A licensed mortgage banker will be an advocate in many areas, including watching the market for you, to ensure that your loan is locked at the right time, so that your rate does not rise during the loan process.