Our family of 4 stayed at this place for 4 days. The house is much smaller than you would expect from the pictures. There is no washroom. We had to use the kitchen sink to brush our teeth and to wash hands. I am not sure if this is a standard in Tokyo but this was not very convenient.
Also, the stairs to the second floor are very steep and the railing doesn't go all the way to the top. It is quite tricky when going down the stairs.
The house is clean and nice otherwise, and the price seems right.