We have what we call affluent neighborhoods. That is, beaches backed by multimillion dollar homes. Due to limited access many of these beaches are not target rich. However, when you do hit a target, it's usually a decent piece of bling. Members of the local MD community have pulled rings valued from $10 to 30k from these beaches over the past few years.
That said, the best hunting beaches are the busiest beaches. A decent combo is to find beaches flush with wealthy young adults. Testosterone, alcohol, and beaches are a fantastic mix for treasure hunters. Think Jersey Shore. In fact, that beach is a target rich environment. Find that beach in your neighborhood and life should be good!!!!
As important as where you hunt is when you hunt. A big deal was made on another forum a couple months ago about outing certain beaches. The point that was missed by those doing the outing is that everyone knows about the beach. It's not a secret location. The key to success is knowing exactly when to hunt that beach. What weather conditions will open it up? When is hunting high going to be better than hunting low? Some beaches stretch for miles. Where on those beaches is the best place to hunt? Lastly, in season, when should you hunt, before the depositors show up, or after they go home? Better to hunt a raked beach or better after the beach cleaning crew has stirred things up? Research and experience will give you these answers.