I really liked this place and will definitely try to stay here again the next time I come to Tokyo.

It's a private and comfortable single room apartment with air conditioning, bath, and bathroom in a very quiet residential area of Tokyo, though nearby is a neat street full of shops selling different kinds of fabrics. Unlike many of the listings on Airbnb in Tokyo, this place uses a physical key instead of a number punch, making me feel a bit more secure about leaving my stuff there. It is very easily accessible by foot to the two nearest train stations (10-15 min) and straight forward to get to. Both stations are on the Yamanote line (making all of Tokyo extremely easy to access). Moreover it only takes one train from Narita or 2 from Haneda airports, making the move-in easy. The room also included a bath towel and soap/shampoo/conditioner, taking care of basically all my living needs.

Hisao-san's wife makes a sandwich for you daily in the morning too, which makes for a nice breakfast or lunch on the go. The owner is very friendly too. I only interacted with him in Japanese (am a heritage language speaker) but there were signs in the room with English explaining how to properly sort the trash and other tips as well.

For Tokyo, it is a nice sized apartment and more than big enough for one person. Two people could stay but may require you to move things around a bit but easily doable. Bathroom itself is a bit small though, so if you're really big or tall, it may be a bit uncomfortable.