This was the perfect location for our first family foreign holiday which we and the kids enjoyed immensely.
Les Grandes Dalles is a beautiful hamlet and, pebbles aside, having the beach at the bottom of the street was ideal.
It should be noted that, one small cafe aside, there aren't any shops or businesses within Grandes Dalles itself; there are a few shops in Sassetot a mile or so away, and Carrefour supermarkets at Cany Barville and Valmont - about 20 mins drive to each. There are a few more amenities at Les Petites Dalles and a slightly bigger beach.
Les Grandes Dalles a great place from which to explore this corner of Normandy and we made excursions to Etretat, Veules-les-Roses, Veulletes-sur-Mer, Fecamp, Valmont - all beautiful. We even managed to have one night in Paris (via train from Fecamp).
The outdoor space was perfect for the kids and the house itself was well-appointed. (one minor concern was that the freezer wasn't cold enough to keep ice cream frozen!)
Agnes was a responsive, sensitive and lovely host, responding to any issues ASAP and helping us retrieve some lost property that we left on our departure.
Overall we really recommend a stay here, including to British people - the road from the ferry terminal at Dieppe is quick and quiet.