I travel with my wife to Venice and we stayed at Rosa's place for 3 nights. Our flight was delayed and we checked in at around 2am. She was in constant touch and helped us reach her place comfortably. She is a great host.
There is a bus stop just at 3-4 minutes of walking distance from her place. All night bus service is available for Venezia.
We went in June, It was hot and there was only a small table fan in our room which was not sufficient. Except that the apartment was really comfortable for us.