This is a great place if you want to visit Amsterdam with kids. The house has plenty of space for the children to play, toys and a backyard. There is a very close tram station from which you can go to all places in the city center in around 20-30 minutes.
Sarah was very kind asking us for our preferences before we arrived. Once there, his father Hans was waiting for us. He was very nice and he also answered our requests via text message promptly.
The only cons that we found is that there were mosquitos at night. But this fixable if you bring or buy some electric repellent.
Altogether, we recommend Sarah's house, in particular for families.