Not being a sailor, it's tough for me to give you a definitive answer to your question. I do have friends that sail, and I have never heard them mention any type of license or permit that they have to go sailing. I assume that any company that rents boats would want to verify your knowledge of sailing to ensure that you can manage the vessel you rent. And they would likely need to give you a briefing on the local waterways.
I think that for the best answer, you should google for a rental company in the location you would like to rent. Then you can go directly to the source and ask them their renter requirements.
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