Let me suggest something I recall from old discussions in the Folders forum - get a folding bike (probably a 20" Dahon, Downtube, or Xoots) and go multi-mode on metrorail or metrobus. For that matter, I think the Montgomery County bus system buses have bike racks (as does metrobus, while thanks to some penny-pinching idiots Fairfax Connector DOES NOT!). While metrorail restricts bikes during rush hour, the restriction does not apply to folders (at least if bagged). Adding in rail or bus to get past bad traffic areas opens up all sorts of locations that may be nicer and more affordable than something close-in.