We stayed at Cristina's for 4 nights during our time in Florence. The place is very central and convenient with shops minutes from the place. Its near the Ponte Vecchio bridge (popular with tourists). The apartment is clean and has everything as described. Cristina was very helpful prior to us arriving in Florence and also during our check in.
The only issue I had with the place was a sofa bed which is not very comfortable but it is expected since it is a sofa bed. However will recommended this place for a quick or long visit when in Florence.