Caterina's flat is simply perfect! Very clean, beautifully decorated, well equiped, well located. And Caterina was also a perfect host. As we were travelling in family (with 2 small kids), Caterina completely understood our last minute changes and was really arranging. Everything was thoughtfully set to welcome my family (specially my 4 months baby).
Just one tip for the travelers not used to European flats : the appartement is on the 3rd floor of a old building. That means that the stairs might be a little challenging for some people (specially because while visiting Firenze you will have to walk a lot, climb many stairs, wait in long lines, etc, = you will probably be very tired in the end of the day ;-)