I showed that I already had a bank account in Thailand, and they did require me to interview about it. But since it was all above board, taxes paid, it was ok.
It took me 3 days , and the interview took me by surprise. My guess is they are trying to find out who is genuine and not. I came from a work permit to tourist visa to DTV, so they seemed to want to confirm many things to make sure I wasn’t cheating the system or planning to work illegally.