For those selling their car, Beepi guarantees a sale within 30 days at a price $1,000 higher than they would get from a local dealer—something it's able to do, in part, because it doesn't have as heavy a cost structure. It determines the price through a proprietary algorithim that calculates how much a particular model is selling for in different areas.
Dan Delima, who lives in Millbrae, California, said selling his 2013 Nissan LEAF through Beepi made sense because of the convenience. Earlier this month a Beepi truck pulled up in front of his home, loaded his vehicle on the flatbed and he was given a check for $20,000.
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"Just meeting one set of people to inspect my car and take the photos was way worth it," Delima said.
Beepi is not alone in racing to alter the way used cars are bought and sold. Driveshift.com is another start-up connecting buyers and sellers online. Like Beepi, it looks to attract customers by eliminating the hassle of visiting auto dealers to negotiate or take a test drive. But different from Beepi, Driveshift.com also offers to bring vehicles to prospective buyers for test drives before they buy a particular model.
More than 40 million used cars are sold in the U.S. each year, with a good percentage of the deals done privately after owners listed their car or truck in a classified ad. Millions more sell through dealers. In both cases haggling for the best price is a big part of the process.
Despite Beepi's guarantees, there is sure to be hesitation from some consumers. Although shoppers are becoming more comfortable making big-ticket purchases on the Web, many prefer to touch, feel or otherwise test products before they hand over their credit card. Conventional wisdom dictates drivers should take a car for a spin before they commit.
For people like Johnson, however, buying a car or truck online is the way of the future. As he looked at the Civic he just bought, he couldn't wait to get the keys into the ignition and take it for a drive.
"It's the moment of truth. I finally get to test it out and see exactly how it works," he said. "I don't think I am in for any surprises."
Questions? Comments? BehindTheWheel@cnbc.com.
UPDATE: This story was updated to include news about Beepi's new round of funding.