I have stayed a little over a week at David's place, it was great, exactly what I needed,
it has everything you'll need, the fridge, kitchen area, shower, the bed was also better than expected,
the location is perfect, Eiffel tower is a walking distance, similar to Arc de Triomphe. There is a grocery store near by.
There is an elevator that helps after a full day of walking. I used stairs only twice and then the elevator.
David responded very quickly and clearly.
I walked to Louvre Museum, Musée d'Orsay and Rodin Museum (different days) from the apartment, so if you like walking and want to explore Paris this way, you can totally do that.
David's place has a lot of books about Paris, I only looked through 'Paris Walks' one but there were all kinds of books.
It was quiet and honestly I had a great time there. Thank you David!