This is a beautiful property in a great location. When it is described as a Showa Era house, I think it really is a Showa Era house. It has been beautifully renovated where needed, but some details of the old house remain. Even though parts of the kitchen were possibly original, they are beautifully maintained and super functional. The garden is lovely, the beds are very comfortable and the extra futons were all new and looked very fluffy.
My only complaint was communication. First, getting there is a bit difficult, only because it is not accessible by car and we were arriving from the airport at midnight.
We had no wifi for the first 2 1/2 days. I got no updates for 24 hours. They let me use another unit to work until ours was fixed. When it came back it was super fast.
Major construction outside our front door, jack hammers, etc., with no notification. This may just be a Tokyo thing. There is always construction going on.
I would definitely book this again.