We loved our stay at Barbara's place. Communication with Nico was great and he meet us and took as to the apartment, walked us through everything, and even gave us great suggestions for food, and set up a water taxi for our return to the airport super early in the morning.
Location is great with this unit, you are literally in the middle of everything, a 5 min walk from the Rialto bridge and maybe 7 min to San Marco's square. Because you are in the middle of everything, there is street noise (there is an outdoor restaurant right outside the building) so expect there to be some noises at night and early in the morning. To us, that added to the charm of feeling like you were part of Venice but for light sleepers, maybe bring some earplugs :-)
Would definitely stay here again.