Claudia's apartment is awesome: a very tastefully decorated apartment on a small side channel in St. Polo - 10 min walk from the train station. We spent very nice days here.
There are two rooms for adults and a children's room including a few toys, which our boys loved. In the very quiet residential house there is also an elevator, which my father-in-law and the boys loved. And in the immediate vicinity there are restaurants, shops, bakeries and everything else you need. In 20 min you can walk to Rialto.
Also the check-in and -out worked perfectly.