Or for an East Coast comparison:
SIN = IAD/BWI/DCA
BKK = MSY
It's your first trip to SE Asia: do Phuket first, and try to include some excursions away from the beach. Then visit SIN for 2-3 days and you'll be blown away by the contrasts.
You can eat for $5 in SIN, but you can also pay well above $70. There is an amazing range of cuisines available. Beer/wine is expensive. Other than working, Singapore's official national pastime is shopping.
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13F