Roberto's place was great. There are no bridges between it and the nearest vaporetto stop, which I greatly appreciated. It's a bit of a hike to the Biennale venues, but quite close to many other things. Despite it being close to a main drag, it was very very quiet, which I also appreciated.
Roberto/Leonella were very responsive. For example, we asked for a bigger knife and one appeared very promptly.
The stairs were steeper than I expected, and there were fewer outlets than I would have liked near the desk, but those were the only things that surprised me.
The kitchen was spacious and well-stocked with cookware and tableware. While the water temperature dropped if two people tried to use the hot water at the same time, because the apartment had a flow-through heater, multiple people could shower back-to-back without the hot water running out.
The wifi was fast and worked everywhere in the apartment.
We were there with another couple, and it was plenty big enough for us. I want to particularly point out the kitchen: we would frequently cook and eat together, and it was big enough for two people to collaborate on cooking, and the table was plenty big enough for four people plus tableware and food. We had a blast.
Overall, it was a great value. If I go back to Venice with another couple, I would not hesitate to rent again.