What documents and reason do I need for a Non-O visa for half Thai children in Thailand?

Will be going to Savannekhet to do a non-O based on half Thai children. As children are out of wedlock I understand I can only get the 90day and extend with the 60 day visit family.

My first question is what is the exact wording I use as reason for visa?

2. From what I was told last year by Today, was just need:

-My passport and copy(main page)

-2 Photos

-2,000baht

- birth certificate and copy with me on it

- house bluebook they are registered in and copies

- Thai mother's ID card and copy

- Thai mother's blue book and copies

- bank statement with 20,000baht (does this need to be same day or can it be from previous day?)

Is this list correct?

Thanks