If you’re looking for a place to stay with a larger group, I would highly recommend Hiro’s home. It was perfect for our group of 5 adults & 1 toddler.
LAYOUT- There are 2 bedrooms on the 2nd floor plus a full bathroom. The bedrooms are separated by a thin wall with a sliding door that can be opened. 2 futon’s fit well in the tatami room, & 2 full size mattress’ in the western room. As others have stated, the bathroom was very nice- make sure you play with all the bathtub settings for the massage function! It also includes a larger washing machine, which was very helpful and we hung dry our laundry in the washroom during the day. Downstairs has a 1/2 bath, common space including kitchen, living/dining rooms. You can easily fit 4 futons downstairs. He provides all the essentials you should need.
ACCESS- 15 minute walk to Osaki & Oimachi Stations, 5 minute walk to Shimo-Shimmei. Convenient public transit access to all of Tokyo. Pocket Wi-Fi and a Maps App is your best friend!