For my entire stay, I only met one of the people responsible for Atelier 5 once for 15 minutes or so, but the apartment was in great shape and everything was well prepared for my stay, so that was all that was needed.
The apartment is also a great place to stay; it has a good location with easy access to the rest of Venice, but still in a calm and quiet place. I would love to stay at Atelier 5 again the next time I visit Venice! :)