Hey, i actually live in Florence (a little out of the town, exactly).
The city is actually really enjoyable and pretty easy to visit, you can walk around all the historical centre in one day.
The classic places to visit (and to take some pictures) are obviously the historical centre (Duomo, Palazzo Vecchio, Palazzo Pitti, Ponte Vecchio, San Frediano, Santo Spirito) and all the areas around. Then, for the sunset, try to go to Piazzale Michelangelo. The best landscape of Florence is from there.
I dont know if i will be there but let me know the exact days you will be in Florence.
Florence, Art by Andrea Magnelli, su Flickr
Florence, Art by Andrea Magnelli, su Flickr
Statues in Historical Centre
Florence, Ponte Vecchio by Andrea Magnelli, su Flickr
Ponte Vecchio
Palazzo Vecchio, Firenze by Andrea Magnelli, su Flickr
Palazzo Vecchio
David, Florence by Andrea Magnelli, su Flickr
Back of Piazzale Michelangelo
Everlasting Sunset by Andrea Magnelli, su Flickr
Sunset from Piazzale Michelangelo