We spent two weeks at Fiona's place with our kids. Fiona was very flexible about arrival and departure times. The house was beautiful and suited our needs perfectly.
Things we loved:
-The use of bicycles!
-The safe areas for kids to ride bikes (enclosed parking area and 2-way bike lane in front of house).
-The petting zoo across the street.
-The relaxing outdoor garden.
-Proximity to beaches (10 mn), playgrounds (numerous), grocery stores (5 mn) the center of Den Haag (20 mn), and Delft (40 mn) by bike or public transport.
-Play area with tons of Playmobil and Lego toys that kept the kids busy during rainy days and downtime (we told them the TV was broken and never heard a complaint for 2 weeks!)

Things to consider:
-Location is great for families and/or people who don't want/need to be in the center of the action.
-As in most typical Dutch houses, the stairs are steep so if you have a crawling baby, be prepared to pick him/her up off the stairs about 38 times per day.

We had a wonderful time and our kids are already trying to get us to go back.