What are the requirements and procedures for obtaining a 1-year extension on a Non-O visa based on marriage in Thailand?

My husband just got the non-O visa based on marriage from the Thai Embassy in the US. He will come to Thailand end of January and plan to stay here for a year. So he plans to get the 1-year extension after he got here.

Here are some questions that he would like to clarify:-

1. Is it ok to have 400,000BHT in “Fixed account” or does it have to be “Saving account” only?

2. He is planning to go to CW immigration office… When can he go to do the 1-year extension? Is it 45 days before the date stamped in his passport?

3. I believe that there will be 30 days under consideration after he processes it. Will he be able to travel overseas during those 30 days under consideration period?

4. Is the copy of the ID of the landlord required? I read somewhere in this group but not sure if it is for 1 year extension based in marriage.

Thank you very much in advance. 😊