Unlike PI, where ALL denominations get the same exchange rate, in Thailand $50 and $100 bills get a better exchange rate.

No, you don't want to deal with banks other than their forex exchange windows, and yes, there is a series of $100 bills they won't take.

And no, I don't remember the sequence.

No, they won't take wrinkled, torn, ugly currency, but they will take folded bills.

Can't speak for other countries, but Imagine it's not much different.

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