Small report: Just passed through Nong Khai Immigration (approx 19.00, taking the Vientiane - Nong Khai bus). I've lived in Thailand before, but this was my first visa-exempt border bounce (initial arrival in January, extended in March). I spent 1 week in Luang Prabang before coming back. Upon arriving at the checkpoint, the first policeman sent me to Room 15 to speak to the supervisor. He asked me what I was planning to do and to see a ticket out (which I had thankfully bought in advance), but did not ask to see ฿20,000 or any confirmed hotel bookings. I hope this helps someone.

Edit to add: I had heard anecdotally that flights to neighboring countries are looked at with some suspicion by the border guards, so I booked to South Korea. These are more expensive, but under Korean law all airlines must offer a rather generous refund policy. It might be worth considering this for your own situation as well.

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