One more thing that wasn't mentioned is that they look closely at your bank book ( i did it like 3 days before visa run and put money on account on the same day) and they want to see your monet two or three months ago.
I said that I took my salary from native county and put on an account in thai bank. I repeat it like two or tree times and after that she said OK.
Also you will be questioned by a students and they understand everything. Your "story" has to be smart.
I'm waiting for deccision today. Hope everything will be ok.