SAN FRANCISCO (CBS SF) — A San Francisco-based car sharing service that hopes to compete with the rental car industry has announced a $25 million funding round.

RelayRides, which began as a hourly service for people to rent out their cars to those in need of a rental, is now targeting long-term rentals.

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While the RelayRides service is available in some 300 airports across the U.S., the company says its current agreement with San Francisco International Airport is the model of how it hopes to compete with traditional car rental firms at other airports nationwide.

At SFO, RelayRides has its own offsite parking lot where travelers can park their vehicle for free and out-of-towners can rent them out. Owners earn 10 cents a mile and get a free car wash along with shuttle bus service to and from the terminal.

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A competing car-sharing service, Massachusetts-based FlightCar, also offers service at SFO despite current litigation between the company and the city of San Francisco.

San Francisco sued FlightCar last year in a dispute over rental car fees and taxes along with alleged unfair business practices for using Town Cars to pick up and drop off passengers at the terminal.

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SFO spokesman Doug Yakel told VentureBeat earlier this month the litigation was still in the discovery phase.