This place is located in a quiet neighborhood surrounded by several convenience stores and supermarkets, as well as being about 400-500m away from the nearest train station, Nakanofujimicho Station (which in itself is only 3-4 stations away from Shinjuku). Do note though that it is about 50-60 mins to/from Haneda Airport by train, and Nakanofujimicho Station is on a really busy line.
Tomoko is really quick and prompt to answer our questions, and is a helpful and gracious host. Also, we are appreciative that she was physically around during Typhoon Hagibis, as our stay coincided with the powerful typhoon.
Perhaps this is due to the fact that this is an old apartment, but it is bigger than your average 1 bedroom apartment in Tokyo. It has good amenities such as WiFi (although it can be a little slow at times), washing machine, air-con, plates and cutlery, kettle, even umbrellas and shopping bags. On a sidenote, I found overall cleanliness to be just about average, with the place being a little cluttered and dusty, and cobwebs in certain corners of the room.