The apartment was in a quite and calm place. Very nice spot for those who need to rest nicely. Great room, even though it is small but it is still warm inside it. The tatami is very japanese style. I don't have trouble sleeping on it. You can have like 4 plugs for your electronic devices to be charged. There is TV with local channel. I sleep nicely there.
However, couple days after I arrived, we had trouble with the hot water and the heater. I found it too long to wait until the hot water really came out. I had to skip shower the first night, but then Choco team came by to check the hot water and left us two very cute dounat ^^ very sweet of you.
It is not very far from the Kouenji station. But just to be sure that for 20kg luggage, you need will be having less space to move because the room is pretty small.