You might consider the Non O Retirement visa via the Thai consulate in Los Angeles. No insurance required. You need to show funds in USA equivalent to 800k baht then….. You will need to open a bank account in Thailand and deposit 800,000 baht in order to obtain one year extensions of stay.
The 1). bank letter of account ownership and 2). the statement, can be a few days old. 3) The bankbook must be updated on the day of application. I just did my annual extension to my 90 day non o here in Chiang Mai.
If you are holding 800k baht in a bank account, may I suggest you re enter Thailand visa exempt and then immediately apply for a 90 day Non O visa in Thailand. Then, extend it for a year at the appropriate time. The Non O does not require health insurance and might save you some money that you will spend on insurance premiums.