This is my own house which has 3 layers. It can accommodate 16 guests (20 ppl is fine too). I decorated the house carefully and prepared you with everything you may need in your trip.
House is located in the central Shinjuku, only 7 mins walk to the neared JR Shin-Okubo station. Super easy to get here from airports and to other spots.
Near parks and Waseda University. Great places to hang out as well.