You are allowed to enter if they don't ask. 😅. But if they (either your airline or Thai Immigration) ask you, and you don't have it, they can deny you boarding (airline) or deny you entry (Immigration).
I entered Thailand via Bangkok just over 2 weeks ago from Tokyo. Both the Tokyo check in counter AND Thai immigration in Bangkok wanted to see my departing flight.
I cannot speak to cancer, but if you have insurance, or the means to pay, the private hospitals here are top notch. I definitely feel like I received better treatment here than if I was back home (home is not Australia).
Hmmm... If you have had the flu etc recently, you will WANT to cough to clear your throat. You need an expectorant that will suppress your cough for a short while, but then makes your coughs "more productive" when you DO cough. I have a cough for 1 to 2 weeks after a strong flu.
She must have done a lot of very short border bounces, and spent 8 months in Thailand on mainly exemptions and/or Tourist visas. They ARE cracking down on that type of thing. I just arrived this morning as well from Tokyo, and I was travelling SE Asia last year iand
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of this year, with Thailand as my base, and they checked EVERY stamp I had against stuff in their computer. I DO have an onward flight to Malaysia, and they asked to see that. After over 5 minutes, she stamped me no worry. BUT, the days of people just living essentually living in Thailand on border bounces are disappearing.
You may be able to wing it in Thailand still, but you had better have that exit planned before you arrive, just in case.
Not the bank statement, but you are required to have 20,000 baht or equivalent in your pocket. It is seldom asked, but if they DO ask, don't be THAT person.