I stayed there with my mother (68) and sister (32) and we had beautiful stay.
It is indeed one block from the metro line (the blue) so it is very fast and direct to get into the core of Manhattan, while living in a much fresh, quiet and clean area, walking distance from grat places in brooklyn like the prospect park and the Brooklyn botanical garden.
Clinton Hill is a great location, and there are nice shops and supermarkets just around he corner -most of them open 24h- to buy food and supplies.
The hosts are a beautiful family living upstairs! But you have independent entrance and total privacy.
I fully recommend staying there!!