We enjoyed our trip to Tokyo and this little apartment certainly suited our needs.
While there isn't a lot of room, the empty closet space was great so we were able to unpack our luggage and leave them on the balcony.
The location was great and the neighborhood charming. Not much traffic noise and we never heard any neighbors. It was quiet at night.
The room itself is typically Japanese sized with a one bedroom space minus any doors between the living room and bedroom so it's larger than a studio. The sofa bed was comfortable as was the futon in the bedroom. The kitchen had adequate supplies and the place was very clean.
Wi-Fi worked ok but the battery is showing its age so it died daily after 6-7 hours outside with minimal usage.
Akari was friendly though we only had contact via e-mail. Some replies were a bit tardy but communication was generally ok.
A few things need a clear English explanation like how to dry clothes, how to close the bath tub, and where to put the rubbish. We were sent a 30 page government PDF regarding how to separate rubbish into different categories but it took a lot of communication to find out where the rubbish room actually was.
One thing of interest is that the neighboring building has 8 floors of restaurants and even though it was nice and comfortable outside, we kept the room closed up as it smelled of grilling meat every evening.
Overall, it was a good stay in a lovely location. Probably not large enough for 4 adults but a small family should have no issues.