We had a great stay at Andrea's.
The check-in is easy, Andrea and his roommates are very open and communicative, making you feel at home from the first moment.
The room itself is a nicely decorated, comfartable and spacious attic room, which luckily allows for enough airflow to keep the heat at bay when you leave the doors and windows open. It is situated in a quite spacious apartment with a big common room and a balcony, all of which can be freely used. The shared rooms and especially the bathroom and kitchen are clean.
The location is quite central, close to the Arno river, allowing to reach the historic center within a few minutes on foot.
P.S. Something to keep in mind whenever travelling Florence is the abundance of mosquitoes. Depite the room being stocked with repellants, bringing sprays and cremes is a good idea.