Decent house. Lots of space. Clean and nice. Quiet neighbourhood. Not really a house where it's comfortable to stay inside and relax with a few beers for more than a couple of hours, but purely as a sleeping facility it's OK.
The listing also says only one toilet, but it has two toilets - but only one shower/bathroom.
Good location, just a quick walk from central Shinjuku with all its nightlife, shopping and eating.