Yuka's place is definitely a short walk to the subway station. However, the Hatagaya station lies outside of the Tokyo unlimited subway pass zone. So I used an IC card for my trips between Shinjuku station and Hatagaya station (but the train fare was affordable so there was little concern).
The apartment was really clean and spacious!! Definitely sufficient for two persons and big luggages. There was also adequate space on the hanging rack for my clothes to dry after washing them in the washing machine. The huge umbrellas provided were also a nice touch especially since I visited Tokyo during the rainy season. The bed was also sufficient for two adults.
The bakery below Yuka's place is indeed amazing! The bread and pastries are baked fresh every morning so I didn't have to fuss about where to get breakfast. There is also a Macdonald's at Hatagaya station and a 7-11 opposite so food is easily accessible.