From Lille : A1 and follow the directions Le Touquet, then Abbeville and finally Le Tréport.
From Paris : A1 and follow the directions Amiens, then Abbeville and finally Le Tréport.
At the Ault Onival roundabout, follow the direction Saint-Valéry sur Somme / Berck, then turn left (direction the Falsimagne factory). After 800m, turn left again (near a farm), and the house will be in the bend on the right.