What you thought of: Sunscreen, water bottles, towels, sand pails and shovels.
What you forgot to save for: A sun umbrella. "People are constantly coming up and saying, 'We didn't prepare for sunshine like this,'" says Wyatt Werneth, a spokesman for the American Lifeguard Association.
How to get a good deal: Buy it at home (Target sells them for as little as $5). If you have arrived without an umbrella and are unsure as to whether buying an umbrella or renting is more costly, Werneth says, "Generally, you're [still] better off if you buy it yourself." The only exception to this rule is windy weather. "If you go and buy a cheap umbrella and it's windy," Werneth explains, "it's going to tear your umbrella up, flip it up and blow it across the beach."