We had a very nice time in Florence. The apartment is more beautiful than in the pictures - very spacious and clean - the view from the balcony is spectacular.
However, we also had some issues with the water tank. Even though Annalaura and her friends communicated well and tried to get the tank to work, we did not have any warm water at all during our stay. Reading other reviews, it seems as though this was not the first problem with water in the apartment. Their friendliness and help with restaurant reservations made up for the cold showers though :)
A last note, it was quite loud at night (noisy people in the streets and apartment next door on Friday and Saturday night up to 4am).
Nevertheless, I can recommend this charming Italian apartment.