Fully equipped studio flat, I was travelling solo so absolutely perfect even space-wise, but I think it would be good for a couple too. Amazing area, just off the busy Hornsgatan, I have basically almost never used the underground.
Feeling very lucky that my exact dates were available, would definitely stay again.
P.S. if you walk to the flat with your luggage from Gamla Stan I'd recommend doing so via Hornsgatan, not directly walking up the street of the flat, there's a steep hill to climb otherwise!