Renting a car isn't just about finding the cheapest daily rate—it's about understanding what's actually included, what fees might blindside you, and whether the company will stand behind you if something goes wrong. The right rental choice can save you hundreds of dollars and hours of frustration, while the wrong one can leave you stranded or facing unexpected charges. Here's what matters when you're evaluating car rental companies.
Insurance and Damage Coverage
This is where most renters get burned. Your personal auto insurance or credit card might already cover rental damage, so purchasing the rental company's collision damage waiver (CDW) could be redundant and expensive—typically $15–$30 per day. Before booking, call your insurer and ask explicitly whether your policy covers rental cars, what the deductible is, and whether it applies nationally and internationally. If you're paying with a premium credit card, check the card's rental car protections in writing—some exclude certain car types or countries.
If you're not covered elsewhere, the rental company's CDW costs money but protects you from liability if the car is damaged. Without it, you're personally responsible for repairs, which can easily reach $2,000–$5,000 for a minor accident in a compact car.
Mileage Policies and Hidden Fees
Check whether the rental includes unlimited mileage or if there's a daily cap. Most major companies (Enterprise, Hertz, Avis) offer unlimited mileage on standard rentals, but smaller regional companies or budget options might charge $0.15–$0.35 per mile over your limit. On a 500-mile road trip, that overages could add $75–$175 to your bill.
Also scrutinize these commonly buried fees:
- Fuel surcharges: Some companies charge $2–$5 extra per day if you don't return the car with a full tank, even though you'll pay less per gallon at a gas station
- Young driver fees: Renters under 25 often pay $25–$50 extra per day
- Airport location surcharges: Picking up at an airport terminal can add 10–15% to your total cost versus an off-airport location
- Convenience fees: Some platforms charge $5–$10 per booking on top of the rental rate
Read the terms carefully or call ahead—these add up fast.
Booking Channel and Cancellation Policy
Booking directly through a rental company's website sometimes offers better rates or loyalty perks than third-party aggregators like Kayak or Autoslash, but aggregators do help you compare multiple companies quickly. The catch: cancellation policies vary wildly. Most companies allow free cancellation up to 24–48 hours before pickup, but budget chains sometimes don't refund at all. If your plans might change, prioritize flexibility over saving $3 per day.
Vehicle Condition and Inspection
When you arrive at the lot, don't just grab keys and go. Inspect the car before leaving—take photos of any scratches, dents, stains, or damage on your phone, and report them to the agent. If you skip this step and return the car with existing damage that wasn't documented, you'll likely be charged for it. The inspection takes five minutes and protects you completely.
Ask what condition the car will be in: some companies give you a clean vehicle; others hand you a car with a previous renter's trash or stains. If cleanliness matters to you, ask about their cleaning standards or request a vehicle inspection report in writing before leaving the lot.
Customer Service and Real-World Ratings
Check reviews on Google Maps, TripAdvisor, and the Better Business Bureau (BBB) for each company you're considering. Look specifically for complaints about billing disputes, vehicle condition at pickup, and how the company handled problems. A company might advertise low rates but have terrible support when something goes wrong.
Platforms like Mercoly help you compare and find trusted car rental providers in one place, making it easier to evaluate multiple companies' terms and read verified customer feedback.
Location Flexibility
Some locations are franchised and have different standards than corporate-owned branches. If you're renting in an unfamiliar city, book from a larger, more established branch if possible—they tend to have better inventory, clearer processes, and more consistency.
Frequently Asked Questions
Q: Can I rent a car with a debit card instead of a credit card? Most major rental companies require a credit card for the security deposit, though a few (like Enterprise) accept debit cards with specific conditions—call ahead to confirm, and expect a higher deposit hold ($500–$1,000).
Q: What happens if I return the car late? Late fees range from $25–$75 per hour depending on the company, and many charge a full day's rate if you're late by even one hour, so plan to return it before your reservation ends.
Q: Is it cheaper to rent for a full week than individual days? Usually yes—weekly rates often drop to $200–$350 total ($28–$50/day) versus $50–$75 per day for short rentals, so if you need a car for 5+ days, book a weekly rate.
Start comparing rental companies today and find the right fit for your trip.