Great place! We used to live in DC and this is one of the brightest biggest one bedrooms I have seen (in an English basement). the bed was super comfortable and the queen air mattress also fit in the bedroom - we were also traveling with a 1 and 4 year old). the apt was super clean and well furnished. Would definitely stay here if we were back in dc. Matthew was very friendly as were his neighbors :)
my only comments for other travelers would be that this might not be a great place for someone who is sensitive to scents - both the bed linens and the apartment itself. We just opened windows though.