@Bobby *******
It usually works like this:
Your "agent" takes you to a bank, they open an account for you (by greasing the wheel with the bank manager) you put in 500baht to get it open, give them the bank book and ATM card and pin code. Then you leave them with your passport, the ATM and the bankbook
They deposit 800K baht cash into your account, they get the manager to write a bank letter, they update the bank book, then they pull the money right back out and go get the visa issued in your passport.