I stayed in the Grace House for two weeks during my first visit to Tokyo and couldn't be happier with the fact that I did. If you're looking for a true experience to see what living in Tokyo is like, the Grace House is perfect. Its small but comfy and has every amenity you need (bathroom, washer, sink, air conditioning, etc). The location of it is truly great, right between beautiful Yoyogi Park and a short walk from both Yoyogi Koen and Yoyogi Hachiman stations, which will take you wherever you need to go in Tokyo.
Ken was also an amazing host who went above and beyond for us on our trip and helped us secure tickets to an event, among other things. I would stay here again in a heartbeat if I ever find myself in Tokyo again.