We were 4, stayed for the weekend. The size was just working for us.
One thing that was missing for us 4 girls was a full lenght mirror! Check in with key box is described super simple and works perfectly. Felt very safe too in the 3rd floor. Metro just 1 min infront of the apartment.
The coffee in the street corner cafe calles madeleine was also fine, which was very rarely the case in our case in paris, unfortunately! (So i would recommend starbucks in paris, with an extra shot of coffee as they are very soft.)
The apartment is so charming, got even an insta shot by the window and the red box.
We can recommend.