The last thing tired travelers want to do after arriving in a new city is to stand at the car rental desk and negotiate auto rental insurance with the on-duty attendant. After all, a rental company’s collision damage waiver, which protects against damage to the rental vehicle, can cost between $10 and $30 per day. And while your preexisting auto insurance or credit card benefits may already protect you in some cases, it’s hard to determine on the spot how much they’ll cover.

So is rental car insurance worth the cost? The answer depends on your personal circumstances, including the coverage provided by your personal auto policy, the credit card used to book the vehicle, the car make and model and the country in which you’re renting.

Yes, it’s complicated. “For a little sidebar of a product that’s offered, … there’s a lot to it,” says Neil Abrams, president of Abrams Consulting Group Inc, a global rental industry consultancy based in Palm Beach Gardens, Florida.

Still wondering whether it’s worth the fees? Here’s what to know about whether to purchase car rental insurance:

What Is a Loss Damage Waiver?

Car rental companies tend to aggressively push the loss damage waiver at the checkout counter. But savvy travelers won’t make a spur-of-the-moment decision. Instead, they’ll have an understanding of their preexisting coverage, how it interacts with what’s being offered and whether it’s worth shelling out for additional protection.

Consider How Much the Rental Insurance Costs

Prices for a loss damage waiver, or LDW, can run the gamut and depend on the vehicle and rental company. Expect to pay $10 to $30 per day, which can add up quickly during the course of a weeks long trip. “It’s usually more than the cost to rent the car,” says Bill Wilson, a Nashville, Tennessee-based insurance expert, chartered property casualty underwriter and founder and CEO of InsuranceCommentary.com. Wilson typically pays for this extra coverage to buy peace of mind and estimates that it adds about 12 percent to the total cost of a trip.

Take note: If you plan to purchase this additional coverage, it can make comparison shopping for rental cars challenging, experts say. Travelers who are especially budget-conscious should click through to the purchase page when comparing rental cars to see how much this optional fee could add to their total cost.

Research Your Credit Card Coverage

Booking the rental car with your credit card may trigger your card’s collision damage protection benefit, assuming the credit card offers this perk, you are the primary renter and you decline the supplemental coverage the rental car company offers.

“The best piece of advice is: Before you go off on your trip, you should check with your credit card company to see on your specific credit card what coverage that credit card offers you when it comes to collision damage,” says Bill Hardekopf, CEO of LowCards.com.

It’s typical for a credit card to offer secondary insurance, which only kicks in after your personal auto policy is applied to a damaged rental car. Some credit cards, however, do offer primary insurance, which means you won’t have to file a claim with your personal auto insurer to take advantage of their protections.

It’s likely worth the 10 or 20 minutes it takes to check your credit card agreement or call your issuer to inquire about coverage levels, limits and other details, experts say. “In general, if you have collision coverage with your (credit card) issuer and your car insurance company, and you pay with your credit card for your car rental, you don’t need that extra coverage that the rental car company is trying to sell you,” Hardekopf says. “That’s pretty much a waste of your money.”

Get Familiar With Your Personal Auto Policy

If you have insurance through your personal automobile, that coverage may extend to rental cars. Again, it’s worth taking time to review your policy or call your insurance agent for the details specific to your plan.

Know that if you do have an accident in a rental car and need to claim reimbursement through your personal auto policy, you’ll be dealing with your insurance company, including paying relevant deductibles and potentially seeing an increase in your auto rates. “If your personal insurance were to cover a car accident on a rental car, you’ll be paying one of your deductibles, either collision or comprehensive deductible,” says Fabio Faschi, property and casualty team lead at Policygenius.

Consider Exclusions or Restrictions in Coverage

Before you opt to bow out of the rental company’s loss damage waiver and use your own preexisting coverage, experts note that you should be aware of pricey gaps in coverage, which could add up in the case of an accident.

For example, having access to “diminished value coverage” is the No. 1 reason Wilson says he buys the rental company’s loss damage waiver. If the waiver covers diminished value, it means that the driver won’t be on the hook for a reduction in the automobile’s resale price after an accident. “I’ve never seen a credit card that covered diminished value,” says Wilson, who notes that renters could owe thousands of dollars due to this claim.

In addition to coverage gaps, experts note that people may want to think twice about opting out of the loss damage waiver if they’re renting a vehicle that’s substantially different from what they own, such as a truck, luxury car or motorcycle. In fact, exotic cars, large trucks, recreational vehicles or motorcycles may not be covered at all under your existing insurance policy or credit card agreement, experts say. You may also want to consider opting in if you’re renting in a foreign country or for a long trip (Your credit card coverage may only last a few weeks.)

Think About the Hassle

Those who recommend purchasing loss damage waivers, like Wilson, note it’s typically a smoother process if damage is done to the car. If it’s a relatively straightforward accident, you may simply hand off your car to the rental agency and be on your merry way.

If you opt to use coverage from your credit card issuer and personal auto policy, you may need to pay for damages out of pocket, then battle with your insurer or credit card company for reimbursement. Buying insurance through the rental agency can help you avoid filing additional paperwork or haggling over tacked-on expenses, such as administrative fees, towing and storage charges.

If you decline the damage waiver, be extra careful in inspecting the car before you drive off the lot, including taking photos of the vehicle’s exterior and interior with clear images of the lot in the background, Abrams says. You don’t want to end up on the hook for damage incurred by a previous renter.

Take Note of Whether Your Employer or Tour Company Protects You

If you’re booking a rental car through your employer’s account or a tour company that includes rental cars as part of the cost, ask about the contract the company has with the car rental agency. You may find that they have already negotiated a deal that includes a loss damage waiver or other protections.

For most car renters, making an informed and savvy decision about whether to sign up for the loss damage waiver isn’t a quick decision. It requires an understanding of your preexisting auto policy, your credit card benefits and the product offered by the rental agency. Says Faschi: “It all stems from understanding your personal coverage first.”