If I'm traveling to a resort in Cancun, Mexico, do I need a power adapter/voltage converter different from US?

I need to figure out if my US appliances will work without any special power adapter or voltage converter....

most definitely and insist on bottled water in your room.

i think you do

Take one. You just never know. Who knows you might end going somewere elce while you are there?

No. Mexico uses the same voltage and power plugs as the US.

Cancun is almost like a little US city. It's very touristy and you can pretty much find everything you'd expect in the US. Also, nearly every (if not ALL) hotels have potable water. It doesn't hurt to ask the reception desk at the hotel, just to be sure: it's called "agua potable" (pronounced agua poe-taub-lay)

The link below might help with other questions.