To start with the positives, the studio has a great location, and at least the bed had a clean sheet on it.
In terms of negatives, there are several: the studio is not very clean- there are several dead mosquitos and traces/marks on the walls, the only window opens onto an internal courtyard that has a closed roof - so it's impossible to have fresh air entering the studio, the studio is very dark/sombre compared to the photos on the website, it is poorly isolated and there is lots of noise from the stairwell etc, the kitchen tap leaks all over the worktop, the kettle when plugged in blew the fuses in the studio (pretty dangerous), the studio was extremely hot and the "air cooler" that was provided, has no cable and so doesn't work, there were no coffee capsules, soap etc (even though they were advertised as being 'mise à disposition'), the bathroom has a damp problem....
I had no reply when some of these issues (blown fuses in studio, lack of cable for air cooler, leaking tap and lack of soap/coffee capsules etc) were emailed/texted to the owner/agency dealing with the studio during my stay there.
To summarise, other than it's great location, there is nothing particularly positive to say about the studio. I've stayed in many airbnbs in my time, this would have to be one of the worst, particularly in terms of value for money, poor cleanliness and the lack of reactivity/help from the host to deal with the issues.