I did not get to meet Marianna but she organized everything for my arrival and had a friend of hers coming to welcome me at her place. There were also jams, biscuits etc for my first breakfasts. During my stay she answered rapidly all my enquiries through messages.
I chose the accomodation because I wanted to be close to the Central Station in order to visit the surroundings area and it is indeed very conveniently located: 15-20' walk from the main train station and not even 5' to the closest metro station (Pasteur). That being said, if you like to chill and enjoy a coffee outside I would recommend to rather go downtown or in Isola neighbourhoods.
Regarding the flat, it is tiny (especially the kitchen) but thanks to Marianna, everyhting is well organized and the decoration is charming. There are 3 rented rooms and each of them has a designed space on the kitchen and bathroom shelves, in the fridge. It is quiet, I did not hear neighbours or the other guests. Wifi was mostly > 50 MBps, steady and having a desk and chair in the room was great to work. The window in the room is on an inside courtyard: there is not much air circulation and without aircon the hottest days (>35°) are hardly bearable. If you have valuables, be aware that there is no lock on the room door but there are 2 of them to get in the building and one on the entrance door to the flat.