My brother will be getting married in Thailand at the start of 2018. To be fair he's giving us plenty of notice but we're really concerned about the cost. We're a family of 4. I don't even know where to begin with regards pricing it up. Should we use an agent or can we book it ourselves? I always just book (European) holidays myself but have never gone this far away. If anyone can advise where to start looking I'd be so grateful. The destination is Koh Samui. Thanks.