I was in Chez Zany for 4 weeks and it was a great experience! Leo, Lu and Julia are awesome people who will help you to feel comfortable in the house and recommend local experiences in Río.
The location of the place is a 10, because is near all the main attractions, metro & bus stations, supermarkets and the traditional "feira" on Sundays, but in a quiet street that will make you feel at relaxed at home.
My only comments are related to the wi-fi connection, that during my stay failed a lot and the cleanliness of the shared spaces, that can be a lot better.