Hi Grace, only 9 days, I am excited for you. What I generally find is that most lotions and roll-ons dont travel all that well in the non- pressurised confines of the baggage compartment and tend to leak, so whatever you take, pack carefully. We used to take them in our hand luggage, but they are pretty fussy with what you can take on board these days, unless you buy them in last chance duty free after passport control. I have always found suntan/after-sun lotions to be pretty expensive in most of the "tourist zone" shops, for obvious reasons, so it will be more of a convienience thing rather than a money saver if you choose to buy over there.

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I love Thailand this much