I stayed at Alexis' place for 5 nights. Small bedroom in an appartment, but enough space for two persons. It's located above Gare Montparnasse, but it's quiet, you don't hear a lot of noise of the streets nearby. Alexis is a very friendly host, I liked staying at his place! If you're interested, he would show you around. You can use the whole appartment, there's a kitchen, a bathroom, seperated toilet an the living room. A supermarket ist located directly across the street. You have to walk to the Metro about 5-10 minutes, but then there are good connections in all directions. Would definitely come back!