For the sim card just get a tourist sim and after a while try to change it to postpaid. AIS seems good enough. If u want he 12 month extension of stay its 800kb, easy to get if over 50. I will get criticized for saying this but: 1) Your state pension will get frozen when u move to TH. 2) The tax laws in Thailand have changed now you are taxable if u are here 180 days, all uk pensions except civil service pensions are taxable. 3) Review all your assets before you become resident. watch carls vids to help ypu get upto speed with taxes. Or maybe you are going for the LRT?
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