I recently traveled with my rather frail, elderly parents to DC to sightsee. I called the night before to confirm an accessible room. No problem. We had two 1 bedroom suites. They were roomy and well laid out for privacy, with the bathroom separate from bedroom and sink area separate from toilet/shower room. The desk staff was extremely friendly, helpful at every turn and responsive to our needs. My parents were thrilled with the visit and really appreciated the friendly service staff. I'm Platinum and asked for upgrade to 2 bedroom suite on the weekend (not available during week). It was awesome and we couldn't have been happier with our stay. I would especially like to recognize Pam, who seems to work 24 hours a day. I don't remember other names of desk staff, but kudos to all. Breakfast every day and social hour in evenings on Mon-Thurs was better than usual Residence Inn fare.
Warning, there is construction in the area. My GPS was confused a bit. I would recommend taking hotel shuttle to King Street. The driver knew short cuts to bypass the terrible traffic. That service ends at about 9 pm on weekends. We ended up walking back a little late after dinner one night (not the parents) and it was a nice walk. I know there is a metro station within walking distance but we had a car. Parking is rather expensive and the garage was full at times. We had handicap sticker so it didn't matter, but might be an issue.