I'll start with the positives. Excellent location, right next to Uffizi which is lovely if you want to check out central Florence. I did find the apartment a little dirty (stray hairs in the bathroom, old furnishings, stains on headboard,etc.), host was a little hard to reach due to his busy lifestyle, and it was very warm without air conditioning in the summer. Of course you can open the window but bear in mind it is a very noisy area - but the latter is the price you pay for staying so close to all the action in the center of town of course!
All in all, I would only recommend to people who don't think cleanliness is of the highest regard, for this price it's a really great location.