This house is beautiful, extremely comfortable and is in the best location possible. We stayed there for three nights with a total of six people (two daughters 7-11 and two grandparents) but there was so much space that we never felt tight. The house is very clean and looks inside as brand new (all windows, doors, walls seem extremely modern and new). My parents stayed on the first floor where they had their own bedroom and bathroom and were next to the kitchen, so they had their independence. Our daughters also had their own bedroom (with really nice bunk beds), next to our bedroom, on the second floor, with a second bathroom. There's so much space and everything so nice that we actually wanted to come home early to relax after some very long walks in Venice. Our daughters have asked us to come back to the same house, which we'll probably do if we visit Venice again.
One extremely important thing to know about Venice (if you are visiting for the first time) is that there are very few grocery stores around. This house is also in a prime location where it is within two walking minutes from one of the few supermarket stores around. Also a bakery and ice cream stores are right there as well. We were within walkable distance from the Rialto and St Mark piazza as well as every other popular place in Venice and yet the house is in a quiet street where there is no noise and everyone could sleep beautifully.
Finally, Marisa was a terrific hostess. While she was out of town during our stay, she made sure we were taken care of, and she replied very quickly to all emails. We are very happy and grateful to her.