The building and the stairs to the apartment need to be restored. It can scare you and give you a terrible impression. However, once you are inside the apartment, it is completetly different. The apartment is really clean, in good conditions and it has everything that you need. Stella is super helpful and provides you valuble information that makes you trip a great experience.
Regarding the location, it is 20 min walk from Notre Dame or two metro stations away! Excellent location!