Valerie's place was lovely and as described. It's a large space for a solo traveler or couple and very pleasantly decorated with all necessary amenities. It is on the 6th (read: 7th) floor so steps must not be a problem. There also was no AC, which was ok in May/early June, but I could see being an issue later in the summer.
Valerie arranged for me to get the keys from her neighbor which worked out well and left notes explaining where things where and how to use things which was very helpful!
The neighborhood of Butte Montmartre is vibrant and picturesque, it's only a few blocks from the apartment if you take Rue Custine north. You are walking distance to Sacré Couer, many boutiques, pâtisseries, cheese and butcher shops, etc.. Note that if you walk the other direction though, you will be in the area around the Barbres metro and it is not quite as nice and very busy and at times, overwhelming. I chose to avoid that metro when I could. Otherwise, the apartment is very centrally located and easy to get to all sights in Paris! I spent a wonderful week and was very happy with my stay! .