You can also rent them at the beach, but I dont know how much they are. I think it would be better to buy one at a store, just be sure you have the little holder that you stick in the sand to put you umbrella in.
$30 dollars at Walmart.
Tybee had a a rental station right by the peer, not sure what items they offered.
Try Burke's umbrella rental. And they deliver. $20 for one umbrella $30 for two chairs and one umbrella.
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