Would you let a stranger with a smartphone rent your car for a few hours? A San Francisco startup that recently came to Boston sure hopes so.

Getaround, which quietly began operating in Boston in March and started advertising in the market this month, lets car owners rent their vehicles fora few dollars an hour.

It might sound like a recipe for horror stories of crashed or stolen cars. But according to founder and chief marketing officer Jessica Scorpio, because car owners get 60 percent of the revenue, it isn’t a tough sell.

“Cars sit idle 93 percent of the time yet are the second-largest household expense,’’ she said. “You can own a car, have the car you want, and have it pay for itself. Basically the benefits outweigh the potential hassle that comes with it.’’

The company certifies that users’ drivers licenses are valid and insure each vehicle up to $1 million, she said. The vehicles must pass a company inspection to be put on the platform.

Want to rent out your car while you’re at work? The company will install technology that allows the car to be unlocked with a phone.

Getaround has raised $85 million since it debuted in 2011, including a recent $45 million round highlighted by an investment from Toyota.

So far, about 50 car owners have signed up in Boston, the company’s sixth market. Nationwide, Getaround has about 500,000 users, Scorpio said, and is also active in Chicago, Washington, D.C., Northern California, Oregon, and New Jersey.

It’s easy to invite comparisons to ride-hailing companies like Uber and Lyft, which have upended taxi and livery services by letting car owners provide rides to smartphone owners. But Getaround is more like the home-rental site Airbnb, with users offering private property for rent rather than a service for hire.

Its most obvious competition is based in Boston: the hourly car-rental service Zipcar. Unlike Getaround, Zipcar owns its vehicle fleet, and Scorpio said Getaround can offer cheaper hourly prices as a result. Getaround prices in Boston were as low as $4.30 an hour Tuesday, she said.

Zipcar, which was acquired in 2012 by a traditional car-rental giant, Avis Budget Group, already competes with Getaround in other markets. Spokeswoman Lindsay Wester said Zipcar isn’t worried about Getaround’s Boston debut.

“As a leading mobility provider for the past seventeen years, competition isn’t new to Zipcar,’’ she said. “We remain keenly focused on meeting the needs of our members in the over 500 cities and towns in which we operate, including here in Boston.’’

Getaround was not the first company of its kind. A similar service, RelayRides, allowing car owners to rent their cars, was founded in Cambridge in 2009 and launched its hourly rentals the next year. That company has since changed its name to Turo, moved to San Francisco, and shifted its emphasis to multi-day rentals, rather than hourly offerings.

Sharon Faulkner, executive director of the American Car Rental Association, a trade group representing traditional rental companies, said the organization “welcomes all new transportation alternatives, including new technology-based businesses entering the car-rental market.’’

However, the group says companies like Getaround should pay taxes and fees levied for traditional rentals.

In Boston, that would include a $10 surcharge that since the late 1990s has helped fund the Boston Convention & Exhibition Center. Consumers pay the fee each time they rent a vehicle in Boston, while Zipcar customers pay that fee once per year.

Getaround does not intend to charge users that fee, Scorpio said.

At least three states — California, Oregon, and Washington — have passed laws explicitly legalizing peer-to-peer rental companies like Getaround and Turo. The laws set insurance requirements for the companies and allow owners to rent their cars without holding a separate commercial insurance policy, provided they are not making more money renting the vehicle than the costs associated with owning and maintaining a car.

Adam Vaccaro can be reached at adam.vaccaro@globe.com. Follow him on Twitter at @adamtvaccaro.