I had an express trip to Paris and had to solve my accommodation a night before my arrival. Marc was the only one able to arrange everything for me, and I'm glad I stayed at his apartment! The studio is comfortable, clean and fully equipped. Location is perfect to move around the city, very close to Marais and the Pompidou. Metro is right away, and there's a Vélib' bicycle station around the corner. I got to meet him, his girlfriend and the cleaning lady and they all were very helpful! Only "drawback" would be the fact that you will have to do some exercise both walking up the stairs and getting to the bed, however I was more than happy to do it.
Paris is even better when staying at Marc's apartment. Highly, highly recommendable!