Well if you are concerned about cost of living.. DC shouldn't be high on your list
Even way out in our suburbs, many drive an hour to work simply because they can't afford to live near where they work
And I'm not talking about 'commuting to the city' - I'm talking about can't live in suburb ABC, so you live in BFE county and commute in.
Anywhere nice in the DC suburbs costs a fortune. Not SF or NYC... but considering I live 45mins from the city and still have those kind of urban comparisons... that should tell you something
Of course you could move out to the country here.. we have really nice stuff out to the west.