Listen mate. I know what I need and want. If you have a child out of wedlock but are named on birth certificate then you are NOT the legal father of that child, hence zero paternal rights. Immigration will only accept an extension of stay based on having a Thai child if you married the mother, (automatic parental rights) you go to court to gain parental rights or you can go to any district office with your child (if they're old enough) and they will grant you parental rights.
Please only comment on issues you actually know about.
Regarding financial. Yes there are two options, either the agent goes with you to transfer the 400k to update bank book which is returned immediately, or they can "bypass" this step with the IO.
CLEAR ENOUGH FOR YOU?
Also please only comment if you have experience or know an agent that deals with SAMUT PRAKAN IMMIGRATION.
Thanks