What are the requirements for a marriage extension visa in Thailand regarding the 400k bank deposit and Kor Ror 2?

To apply for a marriage extension visa in Thailand, you need to show a balance of 400,000 THB in a Thai bank account in your name, which must be deposited at least two months before your first application and three months before subsequent applications. A loan is acceptable as a source for this amount, and the funds do not need to be transferred from abroad. You will need a letter from the bank, which should be issued no more than 7 days before your application, and an updated bank book on the same day of the application. Additionally, it's advisable to get an updated Kor Ror 2 (marriage registration copy) from your local amphur, confirming that you are still married. No witnesses are required at the immigration office for this process.