Really enjoyed staying at Nobu and Tatsuya's space. The location is great -- it is in a quiet area, so no issues with noise, but the walk to shibuya or omotesando/harajuku is no more than 10 or 15 minutes. From shibuya you can get anywhere in tokyo easily by train or metro. There is one set of steep stairs to navigate right by the apartment, but that would only be an issue if you have large, heavy luggage, and in that case it will only be an issue once (when you leave with your luggage).
It is a small place, but it was very clean and has small refrigerator, heating element, and washer/dryer - the basics that you need. The wifi worked well. There is a 24 hour convenience store down the hill, not more than 5 or 6 minutes away by walking.
For travelers who are not familiar with Tokyo, I recommend getting to this place from Shibuya station, either the JR Shibuya stop or one of the stops for the metro system in that area. If you come via JR, at Shibuya station use the "Hachiko" exit (there are other exits also) and then follow Google maps directions. For a reference point, the apartment is very near the New Zealand embassy in the Kamiyacho part of Shibuya. It is literally a 1 or 2 minute walk from the New Zealand embassy down a small street and then down the steep steps to the apartment, so if you can find the embassy, you are almost there.
But Google maps directions to Yoyogi-koen station, another station that is nearby, are not so good. Google maps does not realize there is a fence right by the apartment that you can not pass, so keep this in mind if you come from or go to that station from the apartment.