Staying at Mat's apt was a wonderful experience. I didn't get the chance to meet Mat, but he was very responsive and helpful during our stay. The location could not be better, right in the heart of Marais. I took a little walk in the neighborhood every morning to buy breakfast and my wife would cook, then we had a bit of cycling with Velib to explore around, although we don't speak French at all, it was like we were having a life in Paris, and it felt great! Mat's apt is not big, but has everything you need. The neighborhood is convenient, full of bars, restaurants, cafes and grocery stores so you wouldn't feel isolated. It's 6-7 mins walk to Hotel La Ville Metro station, but there is a Velib station right at the corner of the block where you can rent bikes. But returning the bikes is a bit tricky because nearby stations are always full. It was a lovely experience in Paris thanks to Mat and I will definitely come back again.