Franck is very nice and accommodating. He allowed me to check in earlier than the usual time and he was very responsive before and during my stay. The flat is very central, you can get to any place in Paris in a very short time. It's also pretty quiet and very bright which can be a luxury in central Paris.
However there a few things that are worth mentioning.
The appartment is not always practical. In the small kitchen, you can't really put 2 pans on the hobs and it's difficult to wash your dish in your sink as the space is small.
Also, the flat could be more comfortable. The couch is a single bed put against the wall so when you want to lean back against the wall, the bed slide underneath you.
Finally, it would fair to indicate in the description that the flat is located on the 4th floor without elevator. Not so easy for people with big luggage.
Nothing is really serious but
I think it's a good place for a short holiday but it can appear a bit uncomfortable for a long stay.