We were a group of 7 adults (3 couples plus 1). The apartment has 4 private rooms and a large public space which was very comfortable. The apartment was clean, very well equipped (including many Nespresso capsules), we lacked nothing!
The location is excellent in the Marais (2 metro statios within 5-6 minutes walk) and our host Mathilde's willingness to let us bring luggage early and get out late, was a joy.
Two minor drawbacks, (which can be easily fixed by Mathilde), were that there was no curtain in the window at the entrance to the apartment in front of the first bathroom / shower, and the curtain in the 1st bedroom blocked the windows from opening.
Although the apartment is not cheap, if you can afford it, we highly recommend to rent it. We would be happy to stay there again.