I don't know where you're from, but metal detectors have never been cool around our parts. If you want scrap metal, just hit the junk yard; if you want spare chage, do some chores and you'll be justly rewarded. I reckon there's some charm about finding coins and other "hidden treasures", though.
Just in case there really is buried loot somewhere in them beaches, make sure you find them without looking like a dork. Ditch the large metal detector with full-size headphones and put on the Metal Detecting Sandals instead. It's a subtler approach to looking for dropped coins and jewelry in the sand - which you'll need since you're probably too old to pass the hobby off as a childhood fancy.
With a copper coil built into one sandal that's powered by a battery pack (9V) attached to your calf, these foot accessories will ably take the place of those old detectors that look like smaller home vacuum cleaners. Once you step on an area with metals up to two feet deep, your sandals are going to find it. Rather than make an odd beeping sound, though, it's going to inform you in a similarly discreet manner via sandal-installed red LEDs that flash while the footwear gently buzzes and vibrates.
A new battery should last you up to six hours of strolling down the beach - hopefully, that's more than enough time for you to find buried riches if there really are any. Modern day treasure hunters (like you, I assume) can get the Metal Detecting Sandals right now for $59.95.