We stayed only one night at Rosina's, but it was perfect. She is the most amazing host, very cheerful and sweet. She welcomed us to her home, invited us to a cup of coffee and presented us to all her family, she took of her time to explain to us all the important things to do and see in Florence, she even drove us to the view in Michelangelo's.
The appartment was very nice avec clean, big enough for four people, perfectly equipped, even better than the pictures shown in airbnb, and it's location was perfect, we didn't need to take any transportation, everything was walking distance, even the central station (15min walk).
I will not hesitate to come back there, our journey was perfect thanks to Rosina.