Matthias's place was exactly what I needed for my stay in Paris. The place was clean and the bed was pretty comfortable, hard to stand up in the morning :) plus the room had additional dark blinds. I was able to check in prior to the normal check-in time. Matthias was pretty responsive and helpful with that. I recommend this place!
Few notes for other travelers which was fine with me. You share the bathroom with the host; and the shower and toilet are in different areas (it was the first time I saw this set up). Also, the apt is on a 3rd floor so be ready to climb some stairs with your luggage. I was traveling with a backpack so I had no issues with it. There were two train station walking distance from this apt, but still a 30-40 min ride to all the attractions, so be aware of it when booking.