We have a "deli board" sign outside of our office that can have different messages entered. If we want to indicate something generic about mortgage or home equity line of credit loans, do we have to include the "equal housing lender"? Example would be "Come see Joe Officer about our great mortgage loan rates".

Yes. There is no exemption for such signs.

Your "deli board" should probably have the EHL logotype (which includes the doghouse graphic) as part of its static display.