There is a bus directly from Burri Ram to Chantaburi, or you can go from Prakhon chai bus station to Long Sang and chact the bus there it is 60 km shorter than Burriram. From chantburry,to Trat eller koh chang you can find a bus fra the busstation or wait. It takes about 6 hours from Prachon chai to Chantaburi, and 1-2 hours to a boat. to Cho Chang.