In that case, go to the coordinators page at SWALIFE->Flight Ops and choose your domicile. They generally have parking and commuter info. If that doesn't work, call the BWI flight ops base coordinators. I don't have the number handy or I would PM it to you. They will have the most up to date info handy. I know many of the commuter hotels have some sort of parking agreement.
I thought you were just on personal travel and were being a cheapskate. My mistake!