A friend of mine from Australia is visiting Thailand on 30 days on arrival stamp. He now wishes to stay on in Thailand for a few more days. I'm told that this can be arranged at Chaengwattana at the discretion of the immigration officer. Does anyone know how much this will cost?

He might get an extension of 7 days max. Cost is 1,900 baht and a passphoto. He will need to show a ticket out of the country within those 7 days.

Another option is to go to the border and leave and re-enter Thailand after entering and leaving another country. That wil give 15 days.