In short: A classic, spacious, well maintained, comfortable place with stylish touches, lovely natural light, quiet neighborhood, and park-facing deck. A great location. Communicative and attentive hosts.
More detail: A comfortable and stylish place in a great location. I was attending a conference at the Marriott Wardman Park, and it was a short and scenic walk each day. I also liked the proximity to the Adams Morgan neighborhood (around where Columbia Rd NW meets 18th St NW). So many great options for dining, etc. The neighborhood was great for strolling and looking at houses and plantings (a favorite activity of mine when I travel to a city).
Hosts were great: Quick communications, kind and welcoming, flexible with check-in and checkout, willing to give privacy or (I gather) willing to interact with guests.
And the apartment's space is simply beautiful: Art from around the world used tastefully, vibrant color choices on the walls, lots of natural light, high ceilings, beautiful hardwood floors and trim throughout. It has the charm of an old house (which it is) while maintaining modern standards of comfort (comfortable & large beds, plenty of hot water in the shower, an adequately equipped kitchen). The two bedrooms each have their own kind of appeal. One bedroom is large, including a largish living-room-type sitting area with TV and tons of natural light (in part because of a well-placed skylight, I think). The other bedroom is on the smaller side but has easy access to the park-facing deck off the back of the house, so it is everything I needed as a solo traveler. Both nights of my stay I had some work to finish up before turning in for the night, and the table and chairs in the smaller bedroom were just what I needed.
The space felt private, and I felt at home. Guests have the entire top/3rd floor of the building to themselves. I have to admit that I didn't read the listing closely enough to see that this space doesn't have its own entrance and that the space is shared in that sense. I usually don't book this sort of AirBnB (again, that's my own hangup and the setup is very clearly described in the listing but I overlooked it), but I'm glad that I did stay here. A) The hosts kept to themselves throughout my stay and the place felt as private and secure as if I had my own private entrance. B) Each bedroom has a lock, and securing myself at bedtime gave me peace of mind. Again, that's more about me than this place, but this experience has prompted me to re-think some of my attitudes about AirBnB properties that share an entrance (and some space) with the hosts. Perhaps others reading this will benefit from hearing that. It would be a shame to miss out on this great place. I wouldn't hesitate to stay here again.