Midori-san's place is exactly as described and the space actually exceeds expectations. It is located a 5 minutes walk from the subway station Nishi-Shinjuku and about a 10 minutes walk to the JR station Shinjuku. There is a 7-11 nearby and a liquor store downstairs that sells beverages and simple snacks.
The building itself seems quite new and everything in Midori-san's place is well maintained. The electronics are all of high quality and the AC worked wonderfully in the hot August weather. The rooms are definitely on the spacious side for Japanese standard, and the layout of the apartment had great space utilization. The decor is simple but modern and comfortable. Check-in and check-out were painless, and Midori-san was great at communication.
My friends and I greatly enjoyed our stay and will recommend Midori-san's place to others when they plan to visit Tokyo. Look forward to our return! Thank you.