My kids had a cheap one for years...they loved it found a lot of junk mainly, a couple cool coins and some jewelry. It was not a great unit. No one cares about looking on the beach out here.
Believe it or not, many people return jewelry that was found on the beach to the person who lost it. I read about it in the paper all the time. Guy finds wedding ring with inscription...finds the owner, sometimes it is 50 years later.
The serious units cost real money , you usually see the serious folks each fall scanning the state beaches. Mostly they find pocket change...but every now and again you pick up something more significant