David Chinnery you CAN apply for the "change of visa type" from a tourist visa or a visa-exempt entry, to the 90-days Non-Imm-O retirement visa, after you arrived, on Immigration inside Thailand. The requirements are posted on the Immigration website under Number 9 .. click onto it, a pdf will open. Most important requirement is a bank account, a deposit of 800,000.- THB minimum, and a rental contract
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