The location is the great, very near to the Shin- Ōkubo station. This is a JR line hence traveling to Shibuya, Harajuku, etc is very convenient. Walking distance to Shinjuku too. There are many restaurants, cafe and convenient stores around the apartment. For Muslim, there is a halal corn dog store nearby. If you like Korean idols or Korean food, there are numerous restaurants, cafe and stores around.
As for the house itself, the size is nice for a family of four. The rooms are spacious. There are aircon in the apartment hence it is great for summer. During our 12 days trip, only Naomi apartment provides English TV programs and games. Naomi also provided some coffee capsules, titbits and water for our stay. The washer/ dryer was a great help to us.
The responses from Naomi is fast. She provided great details for the location hence finding the apartment is easy.
In summary, for its location and convenient, the apartment is worth staying.