I am a 19 year old student from the U.S studying in London.
The stay in this appartment was really nice although the room is really tiny. But this did not matter because it was possible to use all the community rooms, too. From the appartment you have a great view on the moloch of Nablus. With taxi and service the house is generally easy to reach but it might be better to contact Bess in advance so that she can tell the driver where to go.
It is even easy to walk to all interesting points in the city. I would really recommend the hammam in the old city.
Bess and her roommates are really nice people and I think you will have a nice stay there.