Renting a car is useful when you first arrive, for trips, or while you wait to buy one. The main companies have counters at airports and offices in cities.
A valid driver's license. With a foreign license, also bring your passport, and an International Driving Permit if the company asks for one.
A credit card in the driver's name. Some companies accept debit cards with extra checks; many do not.
Usually you must be at least 21. Drivers under 25 often pay a daily young driver fee. Rules differ by company and state.
The company places a hold (an amount blocked on your card) for the rental price plus a deposit. The deposit part is released after you return the car, which can take several days. On a debit card, that money is not available to you meanwhile.
The insurance offer at the counter
The agent will offer several protections:
Collision Damage Waiver (CDW / LDW): the company will not charge you for damage to or theft of the rental car.
Liability insurance: covers damage you cause to other people.
Personal accident and personal effects coverage.
Before you rent, check what you already have:
Your own US car insurance may cover rental cars. Call your insurer.
Your credit card may offer rental car coverage if you pay with that card and decline the CDW. Read the card's benefit guide.
If you have neither, as many newcomers do, buying the company's coverage is often the safer choice.
Read the price total, including taxes and fees, before you sign.
Walk around the car. Take photos and a video of every scratch and dent, the fuel level and the mileage.
Learn the lights, wipers and how to open the fuel door before you drive away.
Return with the same fuel level, or pay the company's (often high) price for gas.
Return on time; late returns can add a full day.
Take photos at return and ask for a final receipt.
Prepaying for fuel you will not use.
Toll fees: see the toll guide.
Letting someone else drive who is not on the contract. Insurance may not cover them.