My boyfriend and I stayed at Marinoni's apartment and we really appreciated having a homey and quiet place to go back to after visiting the beautiful but crowed Venice sights.
The apartment has a kitchen (fully equipped - which we did not use, but it seemed fine -- with a stove, refrigerator and a dish washer. There was also an iron and ironing board). The bathroom has some heated bars and I found this essential to get minor laundry done (a hair drier was available). If you are very big or tall you might find the shower a bit too small, but you still can certainly find a way with it (my boyfriend is 1.95m tall and still, he managed it). If you like big towels, you might want to bring your own. The bed in the master bedroom is comfortable. There is a wardrobe with hangers and space to hold clothes of two without a problem.
We have not used the couch in the entrance hall (apparently it can become two beds), except for leaving some of our things (bags, coats, etc) on it.
Overall, I think Marinoni's apartment is a great option for people who would like to stay a bit away from the crowded sites. It is easy to go from there to San Marco and main sites by boat. If you have a map and like to walk, you can take around 30 minutes walking from San Marco.
Marinori was there at the boat stop and walked us to the apartment. He was very friendly and gave us some tips about where the shops and the restaurants nearby are located. He also gave us a map of Venice.
Overall, I strongly recommend Marinoni's apartment and I would certainly stay there again.