Fantastic location in a lovely city, the flat is full of character and an absolute delight, Would definitely recommend to friends at the price we rented it for.
On the down side the agency used is completely inflexible to the terms that are stated on airbnb which is fair enough as at least they do say but don't ask to drop your bags off or turn up earlier than they ask, even if you've a toddler and a pregnant partner as they have agreements with cleaning contractors, etc... It's also not worth asking for any advice as they just replied with some very unhelpful information. The agency also badgered me for an exact arrival time when i'd already given them a very small window. Once the agency were out of the way, we really enjoyed our stay.
Top tip: Hired car from airport and parked it in one of the garages over the weekend (Fri to Sun), which was cheaper than hiring it from within Stockholm itself.