Joachim's appartment is very spacious and functional. I had an overall great stay and I would recommend his place. Communication with Joachim was great too!
The area is not one of the safests in Paris, but it was fine for me. Just do your research.
The appartment did have some issues with cleanliness and the owners belongings being everywhere (for example, I was unable to use the night stand next to the bed, as it was full of stuff).