Near the Pentagon City Mall, there's a Residence Inn. It would be a short trip on the Metro over to the Mall. Since I live here, I don't know the room rates, but I would suspect that VA is cheaper than the District. Also, there are a bunch of other places to stay in Crystal City. Both locations are 1-2 Metro stops away from DCA. The Crystal City area has plenty of inexpensive places to eat as well. Also -- something very close to all of us -- the TSA HQ is located in an office complex right across the street from the Residence Inn. Located at the Pentagon City Mall is the Hyatt at which the TSA held their oft-cited awards extravaganza last year. If you played your cards right, you could avoid a rental car if you stayed within walking distance of a Metro station.