This apartment is stunning! It is a very small but efficient and beautifully decorated! Time has truly been spent to give it that "Wow" factor, and it was definitely achieved. We had 3 adults effectively stay here even though it is tight, but that is typical for this area of Paris. Your trade off is that you can walk to everything!! Notre Dame and the Seine are under a 5 min walk, and you are right in the middle of the Latin Quarter with every restaurant and souvenir you can desire!
The apartment is on the third floor and the stairs are tight and steep. There is a tiny elevator, but you have to climb up 1/2 a flight to get to it, and it will only take you up another flight, so there's not much sense to it. We were capable of climbing up and down with our suitcases though, so it wasn't a big problem for us. We loved sitting in the apartment at night with the curtains open and be able to see Notre Dame all lit up! It was magical! We are highly recommending this flat to any of our friends and family who will be traveling in the area.