We stayed here with our family of 6 and it was comfortable. The apartment is in a great location for walking to many great places within Shinjuku and it was really convenient to the subway line to get around the city. Just a note that the top (3rd floor has by far the nicest, biggest bedrooms) and if you’re coming in the colder months, the bottom floor is really cold. Overall I would definitely recommend Kaoru-san’s place as a great base for exploring Tokyo.