We enjoyed our stay at Jonathan's apartment. The place was clean, and had almost everything we needed for a comfortable 4-week stay. The neighborhood was very quiet, and the apartment very close to Saint Bruno's and Estacade's markets, which meant we had fresh produce to cook almost every day! The main Grenoble train station was also only a 10-minute walk away. We were not as close to the city center as we would've liked to be, but since we love walking, that wasn't an issue for us. Our only complaint, which we also shared with Jonathan, was that multiple times during our stay we woke up by the very loud noise coming from the hallway. It turned out to be the person from the cleaning company that mopped the staircase, but it was very early in the mornings (7AM) and since the apartment is on the ground floor and the bedroom is right by the entrance, this was very uncomfortable. We do not take this against Jonathan, but think if you're a light-sleeper you should have earplugs with you.
We recommend Jonathan's apartment to any Grenoble visitors.