We had a fantastic stay in this wonderful apartment. It has everything inside: the kitchen is complete, the rooms are spacious, the bathrooms are new... and we were just a few steps of Piazza San Marco, but in a quiet street with no noises at all. In the afternoons, we heard sometimes the music of the nearby Conservatory, which gave a great atmosphere... It was on a 4th floor and there was an elevator: it is great not to climb stairs when you arrive tired after so much walking in Venice!
The hosts were helpful and attentive: they gave us some tips about restaurants that were very useful: we had great lunches! And they always tried to help with our needs: they allowed us to leave our luggage in the apartment on the first day (as we arrived before the check-in time) and we were able to leave a bit later on the last day.
In summary, the apartment was great and I can recommend it to everybody.