This is really a lovely apartment, in a nice and central area of Paris. We enjoyed our stay here very much, and have only positive things to say about the place and the host :)
We were five adults spending two nights in the apartment, and we all slept well and felt we had enough space. Also, the apartment was a nice starting point for discovering Paris as the metro stop Charonne is close (5 min walk), and one can also walk 15-20 min and be in the cozy area of Le Marais.
When it comes to our host, we experienced Alexandre to be flexible, kind and easy to communicate with. For example, when we couldn't meet in person to get/deliver back the keys, he organized a good solution for us. I would also point out that we got detailed information about everything we needed to know about the apartment in good time before arrival, which I think contributed to making our stay there pleasurable.
So to sum up - we would absolutely recommend this apartment, and thanks to Alexandre for letting us rent it! :)