Wow!
Nao and Fumihiko, the hosts, are surely one of the best hosts I've ever dealt with here in AirBnB!
But before I get into talking about the hosts, let me share my opinion on the house and location.
We were a group of 9 people, that includes a couple with a 3 years old child. We LOVED the house! All 9 were accommodated into the 7 nice rooms, and each member of our group had his/her requiered level privacy. The bath/toilet to rooms/guests ratio was good enough all members were able to have their daily showers without feeling any inconveniences. The kitchen was spacious and our favorite place to meet, we were able to make a daily breakfasts buffet to gather all in one place before moving on into our daily trips. The house is generally very well and intericatly designed, and was very safe for our child. In fact, it felt safe knowing our child is going up and down between 3 floors. The house had two entrances (front and back), and five out of seven rooms have large windows/exits in case of emergency, with fire detectors all over the place.
The location was perfect for us. There's a bus station in front of the house's entrance, you literally can get out of the door and into the bus in 2 steps. Yet, Japan being Japan, bus and people and everything else is so quite. There are two metro stations around the house (7 and 12 minutes away), and two grocery stores on the way to the stations (Family mart and Lawson). There is a very beautiful large public park right behind the house. The house itself is surrounded by few nice Japanese restaurants, there's one on the right of the house (probably the second or third restaurant, with a beer lamp in front of its door) that I highly recommend. There's no noise or any smells of food.
Now, the hosts were super smart. They've left us with detailed information and enough to not need to even meet with them. Each room had a house manual with details on how to turn things on/off, how to move around the neighborhood, guidelines to follow while in the house or on the roof. The hosts also made sure I receive all map links leading to the house in addition to a step by step images from the near station to the house, images were very handy! Hosts were very responsive, and never left me lost or waiting for their reply. My family and I thank them sincerely and hope we get a chance to meet them next time we're in town!