Mario's place really is in the heart of Venice. There's a small supermarket, a deli, gelateria and bancomat all within 2 minutes walk. The rubbish and recycling point is also close (and congratulations Venezia for having a comprehensive list of what goes where).
Mario met us at the water bus stop and accompanied us to the apartment, and told us everything we needed to know about the place and nearby essential shops.
The apartment is spacious, furnished for people who are going to be out most of the day, but comfortable. Coffee and the other real essentials were provided in the kitchen and that's a big plus. Thanks Mario.