We stayed at the apartment for 3 nights with our three children aged 1.5, 3.5 and 6.5. The apartment looked exactly like the pictures, and was very clean.
The owners even put a pack and play and high chair that were very helpful. They also put a table and four chairs that allowed us to eat comfortably.
Our kids used the room and we slept on the sofa bed, that was very comfortable.
The apartment itself was very nice and had everything we needed, included a great kitchen, since we preferred to cook in.
The location was ok. It is not covered very well by Metro - we mostly did the 1 mile walk to union station (it took us 30 minutes with the kids).
I saw a note that someone did not feel safe to walk there at night - we didn't really go anywhere at night, although in the morning and evenings we always saw families with kids walking there, so we felt fine walking there. The only problematic area is on H street from 4th to 10th, where we felt very unsafe. However, it is pretty far from the apartment. After 10th street H street is very nice, with a number of cool restaurants.

The owners were very attentive and extremely nice, and we will be happy to stay there again.