What a great find.
As stated in the details, you will be sleeping 'local-style' on tatami mats -- which were perfect for us. Steep steps to the second floor made my son feel like it was an upstairs fort. Modern laundry & shower.
Lots of space and excellent A/C (Tokyo hit 35c when we were there but we slept comfortably)
Be sure to explore the neighbourhood, and not just take advantage of the Metro station that is footsteps from the door.
Would not hesitate to book again!