Are online lenders cheaper than local loan officers?

On the whole, no. The interest rate you receive for your loan is largely set by Fannie Mae, Freddie Mac or FHA. So the rates that Quicken, or USAA, or other online lender are quoting are not any different that then rates a local mortgage originator would quote. What they are in fact doing is more of a shell game where they may quote a rate that requires an impossibly high credit score, a shorter term and/or an a lock period that no transaction could ever meet. It is classic bait and switch.