We were a group of four that stayed at Isabelle's apartment. It was very clean, comfortable and had good WiFi. The location is very close to most of the major sites - we walked to everything. Isabelle put us in touch with a private car that picked us up at the airport. The driver helped us with luggage and assisted with the check-in process, which was easy.
There was a little street noise at night, but nothing too terrible. Also, the apartment is on the 4th floor, if you count the ground floor as the first floor (yeah, I'm an American) and the stairs are a little narrow, so it could be an issue for some travelers.