Our host prepared everything to make us feel confortable and at home. He had the appartment ready and very clean. As said in previous reviews, the appartment was just like in the picture; basic super clean, confortable and useful. He also included some free drinks for us :)(a nice gesture from him).
The area is very quiet, safe and convenient, and the metro station is really near (like 2 minutes walking). The only "inconvenience" I found is that the station is not 30 minutes away from Shinjuku Station, as we were told(the busiest and most convenient metro station from the appartment for reaching the city attractions); it is from 45 to 1 hour away, so please consider this distance before you make any plan to go anywhere from Tamagawa (the closest station to the appartment which is 2 minutes away.
The host was nice and kind, though we didn't see each other a lot, as we were out of the appartment most of the time, same as him.
In general I would say the appartment is a good choice if you want something clean, confortable and quiet :).