Nadia's house is very nice. The house has three floors and the guest rooms are located in the top floor, which also has a bathroom and a kitchen for the people staying in those rooms.
There room were we stayed was small, with two beds and a little wardrobe with not a lot of extra space. But the beds were comfortable and since we spent most of the time outside the size of the room was not at all a problem.
Walking to the center of Amsterdam takes about one hour, but there are buses and trams that pass nearby if you don't want to walk so much.
Nadia is very nice and answers fast. She made us feel very comfortable!
I recommend staying at her place.