The crash courses in thailand are really intense (My friend went for it not me) he said its 8 hours a day for 7 days plus 3 days to go around town and practice. He paid about 1k sgd but he speaks well and can read/write basic. Just have to ask for Intensive thai courses from most of the schools. I should mention it was a one on one class but i think its cheaper if you get a few people. Christine teaches at the language academy now i think, im not too sure i took courses with her at cambridge and private tuition.
But if you wanna learn as fast as possible then going to bkk for those 7/10 days might be a cool option.