SUPER HOST!!
Koichi is a nice and kind guy. He always respond the messages quickly. He helped me to solve all the problems and suggested me a lot of things. The biggest problem is my luggage. I had no idea for the place to keep it since i arrived in Japan early but Koichi helped me to keep it when I arrived at Shinjuku Station and brought it to the room.
The room is big enough for 4 people and near a subway station. The room already have all necessary things especially "a pocket wifi". Koichi gave me when I arrived at shinjuku station.
Next trip, no reason not to choose Koichi's place! :)