925 298-6403 belongs to Flight Car a 2012 startup seeking to compete with the established car rental companies by leasing or renting customers' cars while they are idle at airport parking lots or nearby hotels.  Both the owner and renter benefits.
I just returned from a trip to Austin Texas where I rented a car for 5 days at a substantially reduced rate in a seamless transaction that compared favorably with standard rentals. Some minor glitches, to be expected of a new startup, did not materially affect the experience.  Give them a try. You'll wonder why the idea took so long to take hold.