Leo's apartment is very well located - just 2 minutes away from 2 subway stations (Pyrénées or Jordain, Line 11). The neighborhood is awesome: there are plenty of boulangeries, markets, restaurants and lovely stores around. I felt very safe.
Checking in was very easy, thanks to clear instructions from Leo and his parents.
The apartment itself is pretty much as depicted in the pictures. The facilities and appliances worked perfectly. The bathroom though has some big holes on the ceiling and on the floor (which made me a bit afraid of unwanted animals coming in - this never happened though). The apartment was not spotless (specially the kitchen), but on average it was very good for short stays (mine lasted 20 days).
I would just add that the apartment is on the 3rd floor, and the stairs are rather narrow and steep (with no elevator). This may become a challenge to people with heavy/large suitcases. Also, there is no toilet paper. You should bring it with you.
Thanks Leo! Best wishes!