We were a family of five (three kids) and stayed for three nights at the appartment. Everything was as described although the mattress of the sofa bed was quite worn and not comfortable even for two kids. The terrace is great and we used it a lot! Space might be a bit constrained for five people if you have to stay inside.
The kids loved the location as the entrance to the beach is right across the street. We went for a swim every morning before starting the sightseeing tours through Venice.
The boat station to Venice is about a 10-15 min. walk away (or take the bus in front of the house) with lots of connections- we never had to wait more than a few minutes!