You can get a 60 day multi entry visa from the Thai embassy, valid for 6 months. It's applied for online, also you won't be refused entry as you have the correct visa. Or you can apply for a single entry tourist visa if you don't plan on leaving. Just do that every time you need to come here. Better to be refused a visa than to be refused entry after the long flight to thailand. Refusal at immigration means you pay for your return flight there and then or you're stuck in detention till you can board your return flight. Cost and visa types below.
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