We really had a wonderfull time at The "Railyard District Rowhouse" The location is very close to almost everything you need and the neighberhood had a very great vibe. There is a fantastic grocery nearby.
Union Station (and the Capitol also) is in walking distance.
The house is very nice, fancy and clean with great wifi. The kitchen has everything you need. And the hostess Kadija is the best you can have. Very friendly, and when we had troubles with the rental car company, she did much more then you can expect from a hostess. When we come back to DC (and we must, because we didn't see it all), we definately go back to The "Railyard District Rowhouse". Fred and Kadija, thank you so very much!