We had an amazing stay at Alexandre's place. He was easy to reach at any time and quickly responsive too. We didn't get to meet him in person, but we were greeted by his cleaning lady who was super nice. The check-in and check-out was flexible around our schedule, which was perfect!
The apartment was small and cosy, with everything you need. If you look to the right from your bedroom window, you'll see the top of Notre-Dame! A disadvantage was that there was not enough toilet paper for the duration we were staying for, but that's not an issue. Also, no shampoo, but Alexandre offered to reimburse the cost of it! Other than that, it is perfectly located, seconds from Saint-Michel metro stop.
The neighborhood is very busy, full of restaurants and coffee shops. You can walk anywhere if you love walking like we do :)
Overall, would stay there again!