I ONCE rented a car at an agency in a garage under the Villa Borghese in Rome. The parking structure was tight and poorly lighted, and before I even exited I put a dent in the vehicle, thanks to a low concrete barrier I couldn’t see in the rearview mirror.

I’m a careful driver at home with a clean record. But renting abroad poses special challenges, as well as the risk of unintended encounters with foreign objects, which in my case have included an ill-placed guardrail at a tollbooth in Switzerland, a milk truck in Jamaica and hedgerows all over England.

Eventually I decided that dings, dents and scrapes are an almost inevitable consequence of driving in unfamiliar territory, and I resigned myself to buying comprehensive accident protection from rental car agencies. When I travel abroad, I routinely take out a collision damage waiver (which generally covers damage to the rental car, theft, towing and loss-of-use expenses incurred by the company while the vehicle is being repaired), and liability (for injury to people and damage to property outside the rental). These two plans alone can cost up to $30 a day, but allow me to drive away knowing that, whatever happens, I’m covered.

Are You Covered?

People who refuse rental car agency protection plans might call me a sucker. Many of them think that peddling insurance is a deep profit center for big rental companies, most of which have their own repair shops and sometimes don’t bother to fix dents and dings. (For this reason, inspect a vehicle before you take it off the lot to avoid being charged for pre-existing damages.)