We enjoyed our stay at Pierre's apartment. It is small as some of the other reviewers noted, but that was clearly stated in the post and it is on par with apartments in Paris. It an comfortably fit two people, and 3 at most (with one person on the couch).
The walk up to the fourth floor is a bit challenging if you have a lot of luggage (no elevator in the building). The apartment was also clean and a comfortable place to stay.