Robert's house is great to accomodate a group of people. The kitchen is fully equipped, the bedrooms are comfortable, and everything was very clean. The communication with the host was very easy and it was not a problem to check-in late in the evening.
We did not see much of the neighbourhood but it was around 15 min with a taxi to get to Washington downtown.
This is a great value for the price, i would definitely come back there for a next visit with friends in D.C.