The apartment is more or less perfect for a couple, was very clean and had all the basic amenities. We were met by Betty's daughter at the Arsenale station, at our arrival, who took us to the apartment.
Betty and her daughter are in general very serviceminded and very quick at responding, so you don't feel completely on your own with potential problems (f ex we experienced a brief electricity failure in the entire building/area).
The area is really nice, and feels local and relaxed, even though you're only 10 min's walk from the most touristed areas in Venice.
Two minor points of critique; the bed is not long enough for tall people (>190cm) and the wifi was substandard as the router (apparently) stands in the neighbour apartment.