Just a reminder—if you frequently visit Thailand and stay for several months, like some of my wealthy friends, you might want to secure a tourist visa or DTV as soon as possible. That said, even that isn’t always a guarantee, so it’s wise to keep extra cash on hand for immigration officials. Otherwise, you could find yourself in a holding cell or on a flight back to wherever you came from. A French guy I came on my flight with was denied entry, put in the dirty detention room and had to pay $1500 for return flight @ Phuket. 
TLDR : Answer Summary
Frequent visitors to Thailand should consider obtaining a tourist visa or a DTV, as it enhances the chances of entry and compliance with immigration laws. Having additional cash on hand is advisable to deal with potential situations at immigration. Recent changes have made it more complex for travelers to re-enter Thailand without valid visas, as some are denied entry or have been detained, especially those trying to leverage the 60-day free stamp multiple times. Understanding your rights and the current immigration landscape is crucial for avoiding denial of entry.
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