We had a great stay at Constantin's flat--the location is truly amazing, especially considering the price. The pull-out bed was surprisingly comfortable, and the apartment was plenty of space for two people. Although there is a shower and sink in the flat, the bathroom proper was down the hall a ways, which was a little inconvenient, but also classically Parisian. The kitchen was perfectly functional, and the view from the window gently beautiful. We didn't see much of Constantin, but he was very quick to respond when we contacted him with questions, and offered to give us addresses of places to visit and tips for the city. Highly recommended!