The location is very good. It is 15-20 mins walking distance to St Marc's Square and less than 10 mins walk to the Rialto bridge which are the 2 main attractions you will visit during stay in Venice. There are also a lot quite shops, pharmacie, gelateries and restaurants around. It is also 3 mins walk from the Ferry station for the ferry that brings you and takes you from Stazione Lucia to the airbnb.
As for the airbnb itself, it was very clean and organized. Having a washing machine really helped us. As it was our first time in Venice, we were a little surprised to see the narrow streets that lead to the airbnb, and the narrow staircase that lead up to the airbnb. Don't be surpirsed that because it is like that everywhere in Venice.
Overall we had an enjoyable stay!