The flat was in an amazing location. As described by others, the flat is close to very good restaurants and cafes. Everything within the city centre is reachable within a walking distance. The flat itself is nice and spacious.
The only confusion was the parking situation as it was not clear in the beginning. We ended up parking on the street at Lungarno della Zecca Vecchia which is 3-5 minutes walking depending on the parking spot you find. This is the closest you can get to a free parking. It is free at night from 8 pm to 8 am (as of September 2020). During the day it is 2€ per hour. This parking spot is not in the ZTL, so it should be accessible to everyone.