When I visit DC, I usually stay at the hotel on the Gallaudet campus; Annie's place is just south of campus and it was really nice to have a whole apartment to come back to after a long day rather than just a hotel room! This is a great area, with Union Market nearby, and very walkable to some of my favorite places, like La Colombe Coffee, Red Bear Brewery, Seoulspice, and the H street corridor.
One tip for the unit: the central air was almost constantly on when we arrived, but we realized you can close some of the vents on the ceiling to minimize the chill if it's too cold for you.
I imagine I'll be back at Annie's if it is not booked when I make my plans for my next visit!