Our experience with Elena was superb. Elena greeted us on time at the apartment, which was easy to get too (we walked) from the train station. She gave us a run down on local Florence, where to find the best (and affordable) groceries and bakery's. Elena also left us with several maps and a package with details about local restaurants and places to eat.
The apartment was very functional, and was a comfortable size for 2 people with a nice bathroom and good kitchen facilities. The only down side was as it became noisy in the early morning (5-6am) due to garbage trucks and deliveries to the hotel opposite. Even so this apartment is highly recommended, we would certainly return here.