Unless you can show proof of twelve consecutive deposits of 65,000 baht or more in a Thai bank account from a foreign source you will have to have 800,000 baht in a Thai bank on the day of application for your O visa in Thailand, your initial O visa will be for 90 days and then you will apply for a 12 month extension, same financial requirements as applying for the O visa, no need for health insurance for an O visa, OA will require health insurance