Marella is a perfect host meeting is at her centrally located apartment in Florence. She took us through the running of the apartment and gave us a map with some local places she suggested, which were all great especially the central market which is great for food lovers.
Her apartment is exactly where you want to be, a walk to and from everywhere in Florence. It's clean, comfortable and Marella made herself available to anything we needed.
You can't go past this central location. Also buy a Firenze card it gives you priority access to the galleries and free public transport. The C1 and C2 bus are just around the corner.