A very convenient location, close to Shinjuku station, if you have the JR pass, you can easy get to Shinjuku from the airport by Narita express! It's get for you to the center of Tokio 20-30 min.
Here is Wifi, heater and a bath (it was very actual in winter), kettle, mikrowave and refrigerator (but it didn't work).
Good flat but a little bit darkened. It's suitable for two people!