Great apartment about a 5 min walk from the JR Nakano station, which is very convenient if you have a JR Rail Pass (one station on the JR Chuo Line to Shinjuku Station)--though if you're not planning to use the JR, be aware that it's not a short walk to Shinjuku.
Apartment is new and very clean, with AC and a handy in-unit washer. Very comfortable with all the amenities we could need. Would stay again if we're in Tokyo. Thanks!