Lorenzo's apartment is, like many other people have said, huge with plenty of space if you and your group need to spread out. The air conditioning worked great, and everything in the kitchen and bathroom seemed new and were in good condition. The location cannot be beaten. The closest piazza has bars and restaurants but slightly less crowded than the other piazzas. But it is still an easy walk to the Duomo and the main square. I would highly recommend this apartment, especially if you are traveling and need a break from small hotel rooms.
Lorenzo and his mother were also very helpful and understanding when we had to change our reservation and when we arrived later than planned. They were great to rent with!