Your 16-year-old son has passed his driver's education course, and scraped together enough cash for his own car. You take a deep breath and given your blessing, until your agent tells you the rather large amount added to your premium -- just to insure a lousy used sports car.

Why can insurance sometimes cost as much as the car? Why are insurers so tough on kids, or Corvettes?

It boils down to one word: risk.

To an auto insurance company, you are a collection of risks. Your sex, your age, your marital status, driving record, type of car, and place of residence all contribute to an insurer's prediction of whether you'll file a claim. An insurance company can't know, for certain, what kind of driver you are. They can only guess, based on the accumulated statistics for drivers like you. Even if you're a stellar driver who just happens to be young, single, male, and own a sports car, the insurer is probably going to place you in a category with a high premium -- or it may reject you entirely.

The good news is that all insurers don't price risks identically. While insurers are highly regulated in many states, they still operate as competitive businesses, focusing on certain markets and avoiding others. What's more, some operate their businesses more efficiently than others, passing on the savings to consumers.

That means you may be able to save hundreds of dollars a year by shopping regularly, even if your insurer rewards long-time customers. A great quote from a new carrier may trump the loyalty card.

In the following sections, we'll look at some sensible ways to find the best coverage, whether you're age 16 or 86.