@Ed *******
This forum is a southern baptist church. Agents are a Buddhist temple. Why are you expecting Baptists to help you be a Buddhist?
Because all good Baptists know for certain that Buddhists are destined to burn in hell for all eternity.
As an American passport holder, you are eligible for a visa exempt status on arrival.
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Once here I recommend you go to Pattaya and yak with a handful of expats about the rewards, risks and prevelance of using a Visa Agent for people in your particular financial situation.
You will find that many use Maneerats agent to assist in setting up your “non-o” retirement visa and extension, found in Soi 13-2 just up from beach road. And there are others. Might as well use the agent to open your Thai bank account as well.
Keep a good solid US bank account, and open a Wise account and get it all set up before leaving the US.
Buy health insurance from a Thai company as soon as you can. Stuff happens here - 600,000baht hospital bills will ruin your whole day without insurance.
Finally if you let the baptists here scare you out of doing something that hundred of thousands do trouble-free on the regular, consider getting your retirement visa in Cambodia instead. Cheaper and easier than Thailand.