N/A apartment is very convenient for transport as it's within walking distances Shimbamba station (local line not cover by JR pass) only 4mins walk; Shinagawa station is 15 mins walk, very big station easy to access to other suburban areas and last but not least Tennozu Isle station is on the monorail line to Haneda Airport, also around 12 minutes walk.
It is also close to lots of convenient stores and restaurants.
The apartment is perfect for 2 peoples, staying in Nanako apartment you will have the kind of experience on how the local lives.