Great location, in a quiet family neighbourhood but not far from 8th street with shops / restaurants / bars / etc. Only a 10-15 minute walk to the Capitol and the Mall with all the museums on. Eastern Market metro station is about a 5-10 minute walk away with access to the underground.
The flat itself was lovely, very clean and spacious, had everything we needed including a bit of outdoor space for when the weather was nice on an evening. We appreciated things like finding a bag of decent ground coffee & coffee filters when we arrived (amongst other things), made us feel like we were welcome. Margaret herself was great, excellent communication in the run-up to our arrival, and was very accommodating whilst we were there, which was very much appreciated. The flat has all the mod-cons including air conditioning, washing machine, tumble dryer, dishwasher, etc.
Would happily recommend it as a place to stay, had a really good time there and would happily stay again if I was ever in Washington in the future.