You can bank on any where between 30 to 50 thousand baht. Shop around. Just to give you an idea I paid the first time
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that included pick up at airport and following money straight to immigration. Used bank down stairs in immigration building and straight front of line service. With 4 hours I had my no o and the one year extension for retirement stamped in passport. No hassel and for me convience and speed is worth the money if you have it. Each year for renewal
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to
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Bhat and I spend maybe 5 minutes at immigration at most. Everyone is different and everyone has the money to just throw around. But for me it's the only way to do it