The DCL Passporter says snorkel equipment is $25 for adult gear and $10 for kids gear (Mask, Fins and Snorkel) at CC.
I have read several times on this Board that fins-only rental is $15. Snorkel vests are free, using your own equipment or not.
You can buy a decent set of snorkel fins for about $15 at Walmart, Costco, Sam's, Target, etc. You can also use them at other places, like Grand Cayman and Cozumel. If you're worried about transporting them - don't. Buy them when you get to the Cape area at Target or Walmart.
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