Very happy with Arianna's place. Although it's downtown next to everything it's tucked away in a little side street which cuts down the noise substantially. A few things to note: one, it's a 5th floor walk-up so be in decent shape or willing to huff and puff, two, the ceiling entrance to the bed and bathrooms are low (italian size) so beware if you're 6' or above.
It's a great space and I'd probably rent again if I were to stay in downtown Florence.