Baudouin's place was a great appartment for two couples as I was traveling with my wife and her parents. The location, being extremely close to Gare Du Nord, made it very convenient for catching the train or Metro to start your day or head to a new location as we left Paris to go to Amsterdam next. It was also close to some nice streets with great restaurants and it is an easy walk to Sacré-Cœur and Montmartre. We also had a grocery store right on the corner that was extremely convenient.
The building was very safe and secure and the apartment was beautifully decorated. It felt like a Parisian home and we were comfortable there. It was our Paris home! Baudouin was a fantastic host and the communication was easy and helpful. We would stay there again but if you like having the windows open, it can be a little loud at night. We were so tired after a full day that it did not bother us at all.
I would highly recommend Baudouin's apartment as a great place to stay for your Paris adventures.