Great location, very easy walk from the main train station to the flat. Also very easy to make your way by foot from the flat to San Marco square. Has everything you need and the view from the bedroom is fantastic for people and boat watching.
Note that only the top part of the bedroom window opens, the bottom part is locked but it's still a great view.
The location to drop your rubbish off is right around the corner (turn right out of the flat walk all the way down then right again and you'll see the barge if you head in that direction) but you have to be there early otherwise they will in fact walk by eventually.
Very easy to get a boat (Alilaguna) to Marco Polo Airport from the Ca' Rezzonico dock as well.