Sandra's apartment CAN'T BE ANY MORE PERFECT. Comunication before and during the stay was fluent, and there was some fruit, water for us upon arrival ;)
Location: the best, walking distance to all relevant places but yet quiet, since the bedrooms are not facing the street. You can't hear the noise from outside.
Cleaning: perfect also, spotless and very new.
We were 3 people, very comfortable with 2 bedrooms and kitchen with everything you might need. If you don't feel like cooking, trattorias are all around.
If I come back to Firenze (I hope so!) I would definitely go for this apt again.

Only small downside: the entrance can be complicated for old people or someone with walking issues. It's a very short but steep way. My parents are over 70 and it was ok, going slowly. On the other side, it's typical old fiorentin arquitecture ;)
Also, it seems to be designed for parents with small children, since the children's bedroom is not completely separated from the double one. So, you can hear everything.

Thanks, Sandra!