yes tb 800k not usd. Funnily enough I prefer to follow the rules. The rules for retiremnt visa are either 800k in a Thai bank account or monthly receipts. I also suspect once you used an agent you are probably stuck using an agent. I'd prefer not to risk it.
You can get a 3-month Non O visa in London Thai Embassy (online). No insurance requirement. Once in Thailand open a bank account and send $800k from overseas and leave it there for at least 2 months. Then you can get 12 month extension each year. No insurane requirement.
I noticed they had provided a "letter of introduction" and a,pretty lady to sit with me at the bank. An hour and dozens of signatures later to Thai docs I had my card and account.
wouldn't surprise me if part of the fee is shared.
This was the only thing I ever used an agent for after similarly being refused by many banks. The agent staff accompanied me to Bangkok Bank and it took about 40 mins. Cost was about 5k.
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