I stayed at Coco's place for 3 nights, and it was perfect for my needs. As many others have mentioned, it is a steep climb and heavy/large suitcases would not be at all ideal, but as I only had a backpack it was more than fine.
It's the perfect space for one- clean, well-equipped considering how small it is, and felt very safe. The neighbourhood is lovely and quite central, and there is a metro station at the end of the block. If you are traveling in or out of the city via train through Gare Centrale, it is an easy walk down the street.
The toilet is shared, but was always free when I went to access it. It's an old building so you can hear some minor noise from the neighbours, but I was never woken up or bothered in any way (and you are in the middle of a city, so some ambient noise should be expected!)
I would be happy to stay here again- thanks, Coco!