It is located near Hatagaya Station, two stops from Shinjuku, on the Keio New Line. Be sure to note that the Keio 'New' Line is from platform 4 in Shinjuku (at time of writing this) and is different to the Keio Line which does not seem to stop at Hatagaya.
This apartment was well suited to our family (two adults, two children). It is a little cramped in the living space but that's understandable in Tokyo. Great to have the convenience of the washing machine, large kitchen sink and fridge for the family. It's good value for the price and location.