Wow, 1200 THB = 'robbed'
Traveling with my wife and luggage, and after a long day-plus of travel, I like to have someone meeting me with a nice spacious clean car. So I'll pre-arrange to have a car meeting me, and it'll run about 1200 THB. And I'm more than happy to pay that over grabbing a cab.
Now if we want to stay on topic, then how about 'what does SGS charge for transfers?'