Shin was a very friendly host. I managed to meet him on the first night that I reached, and had a nice chat with him. He's always very responsive to questions through email.
The place was prepared with a double bed, a double mattress on the floor, as well as a roll-out bed. For sleep-wise, there was sufficient to accommodate my family of 5 (2 adults and 3 kids), though a little cozy. However, as far as apartments in Tokyo are concerned, the room was quite spacious. Amenities-wise, there's a microwave, bar fridge, TV and internet access (fixed and portable). I thought the description stated a washing machine, but I didn't find one there.
In the immediate vicinity, there are quite a few restaurants and at least 1 convenience store. My kids were having onigiri from 7-Eleven every day. Would recommend the soba place Matsunaga, as well as the coffee joint Hatto Coffee.
However, be prepared to walk a bit, as the place is around 10-15 minutes on foot to the nearest Metro/JR station.