We spent three nights at the submarine apartment and the location was really the best feature for our family with young children. It is just blocks away from a grocery Store and the train station to Venice.
The host is very attentive and answers quickly to our needs. The place was super clean!
Only draw backs for us was the four sets of stairs- you on on the very top floor and the lack of shower soap. The beds were a bit uncomfortable too. Overall we really enjoyed staying there.