Cris & Marco's place was just as described. The location is fantastic, close enough to the historic and artsy parts of the city, but tranquil and safe. The bed was very comfortable, and the room was well ventilated (the AC was a bit loud, but efficient, and hey, AC is a luxury in many European cities, so we are grateful!). Cris was extremely welcoming and helpful, providing great advice and tips to navigate and enjoy the city (from restaurants to little known places to view the sunset). Highly highly recommended!
PS: if arriving by car, mind that there are ZTLs (Restricted Traffic Zones), but also many garages within a block, all of which provide permits to access the ZTL. Call these in advance to reserve a parking spot.