The location, the aircon, having a kitchen and stable strong wifi were all great. We were given tips on local restaurants, the host was on time to meet us, and a Florence guidebook was very useful because we were disappointed in ours.
The only downside for me was the bathroom - it was so-so. Since the building is old, the water takes some time to leave the tub after you take a shower, so the tub stays messy and unpleasant to get back in later. Kept my daily showers to the shortest, hence giving it 4 stars.