We loved our stay at Costanza's wonderful apartment! It really is as spotless, charming and well-located as described and pictured online! Costanza was a friendly, engaging and helpful host who provided us with great tips/suggestions, and even made reservations for us at a favorite restaurant of hers.
Of note, due to the location of the apartment, check-in can be mildly tricky, so get all of the necessary details up front and perhaps schedule an exact time to meet up with Costanza. Also, hot water access can be limited at times - plan accordingly!