We rented this property for a gathering of three families with kids, 18 total including an infant. It's not a mansion, and 18 filled the two units to the brim, but this was a group that isn't picky and just adapted to the space. Having three floors was very convenient- consider the space as 3 hotel suites stacked on top of each other, with the top floor accessed by going outside and in another door.
It was great to have two full kitchens so we could cook food for the group. Kitchen was adequately equipped for basics (toast, waffle maker, pots and pans) but note there is no griddle or mixers, spice racks, etc.
The property is located in an area that at one point was probably not the nicest place in town, but is clearly picking up. We didn't feel unsafe, though others may have a different tolerance for economic diversity. Travel time to sites downtown was good, either driving in or by taking Metro from the Anacostia station.
All in, this is a great property for a group with basic tastes, doesn't care if things aren't perfect (but totally functional), and wanting to have together but separate spaces at a great price. Would stay here again.