Renting a room at Cristiana and Marco's has definitely been an excellent experience for me. I stayed at their appartment for six nights in May. It is well located near all the places of interest and of the congress center (where I attended a conference).
Cristiana and Marco are very welcoming and considerate. I have learned a lot from them about Florence and really enjoyed their recommandations (better than any tourist guide). They also gave me useful information beforehand to prepare my venue. I really envoyed their kind thoughts.
As the whole appartment, the guest room and shared bathroom are clean, pleasant, in a nice shape and well decorated. The bed is comfortable. The room is on the street side with double glazing (it is a little bit noisy but this may be worse in many acommodations in Florence). The wifi works well.
Last but not least, Cristiana prepares a very good breakfast.