Staying at Frederico's was an excellent choice. You can't be better situated in town. Vaporetto stop is at 5 min walk. Places to have small breakfast around. Not in a busy area of the town, so quiet at night.
Before arriving, Frederico sent us all the necessary documentation on how to get to his place. When we arrived, we were welcome by a friend of his who showed us where we were on a map. We had a chat later on with Frederico who talked about how to live in Venice.
The room was very clean. We had our own bathroom. The air conditionning in the room was excellent : not too cold, not too noisy. The mini-fridge in the room was very useful to keep some stuff fresh.
Definitely a place to stay in Venice, highly recommended.