Nadia's apartment is very nice.
It is in a good building (clean and well acousticly isolated), and the apartment is on the 6th floor without lift. Though it sounds bad, it is not - if you are regularly fit, you go up easily, and once you get to the top, the view is quite wide, and it is very calm. You actually wake up to the sound of birds singing! Nothing you would expect in a city like Paris!
The bed is very comfortable.
It has a sofa bed in the living room where our kids slept. If you are 4, it is not an apartment to spend much time in, but it is perfect if you need a place to sleep, have breakfast, and eat something in the evening. It has a table and 4 chairs.
Nadia was very friendly and answered very fast when I contacted her.
Check-in is with code in the main building door and safe box for the house key, which makes it a perfect fast check-in.
So overall, it was a perfect stay, and I totally recommend it.