Since May 2010 we have stayed at Tonwha on four occasions; lovely location on the main street through Chao Lao, cross the road and 100m directly on to the beach. The Chanthaburi coast truly is beautiful, unspoiled compared to much of Thailands coastline. Beach is great for families/children, clean and safe. Tonwha has little chalet/bungalow accomm, 500 baht for a couple and 700 naht for a family one that has 2 king-size beds.
Family owners are nice people, the one time we left booking too late they arranged accomm for us at a competitor.