Even soaring gas prices and a sluggish economy won't slow down the American road warrior. After all, we like to travel whether it's a vacation, family reunion or simply a road trip. Which means time for car rentals.

The rental car company's collision damage waiver/loss damage waiver (CDW/LDW) could save more than your financial stability. First and foremost, educate yourself. Know what's covered by those seemingly steep fees.

A few of the many unknown facts follow:

Loss valuation

The personal auto policy doesn't cover reimbursement for the full value of a car, which many rental car agreements demand. You could end up with coverage of the actual cash value or repair costs (the lesser of the two wins out), which - more often than not - is a far cry from the full value.

Diminution of value

For third-party claims, the Personal Auto Policy could cover claims of diminished value under the "expenses for which you become legally responsible" clause. However, there is a cap on the payout, and many states have approved the endorsement PP 13 01, which excludes claims of diminished value.

Use of vehicles

While older editions of the Personal Auto Policy don't cover physical damage of certain non-owned vehicles - including vans and pick-up trucks - used for business purposes, the rental companies policy doesn't carry those exclusions.

Coverage area

The Personal Auto Policy doesn't cover an insured who travels beyond the United States, Puerto Rico or Canada.

Types of vehicles

Physical damage coverage for motorcycles, pick-up trucks, vans, motor homes and other non-autos isn't covered under the Personal Auto Policy.

Loss settlement

Certain Personal Auto Policy editions stipulate that an insurer has an opportunity to appraise the vehicle before it is repaired. If an ambitious rental company makes immediate repairs, the insured may lose coverage by default.

Indirect losses

The rental car company will probably hold the driver responsible for its loss of rental income. Certain Personal Auto Policy editions only cover loss of income for a theft; others have daily and maximum indirect-loss caps.

Administrative expenses

The Personal Auto Policy usually doesn't cover loss-related fees for appraisal, storage, towing, etc. Rental car companies are known to tack on exorbitant expenses and lump them under "administrative expenses."

The next time you ask for advice about renting a vehicle, weigh the risks and benefits of purchasing coverage from the rental company. The extra $20 per day doesn't seem nearly as ugly when compared to hefty expenses from coverage gaps.