Zipcar’s 673,000 subscribers currently share its fleet of 8,900 vehicles. But what if they could also rent yours? The company announced on Wednesday that it’s taking a first step toward finding out.

Zipcar has led a $13.7 million round of funding in a peer-to-peer car rental startup called Wheelz.

Like similar startups Getaround and RelayRides, Wheelz runs an online marketplace (there’s also an iPhone app) on which neighbors can browse and rent each other’s cars. It’s distinguishing feature is that it focuses on college campuses and restricts members to those with campus email addresses. Students who don’t have cars can rent them from students who do.

“This investment is our first step in the direction of potentially offering a broader array of mobility services,” said Zipcar Chairman and CEO Scott Griffith, who will join Wheelz’s board of directors, in a statement. “We believe our strong brand and first to scale advantage put us in a unique position to exploit the network effects and business synergies Zipcar can bring to the broader mobility space.”

Although Zipcar brought in about $63 million in 2011, its net income was only $4 million. In order to scale, it currently needs to add and maintain new fleets of vehicles — an expensive affair. A peer-to-peer model like Wheelz’s, however, could help it scale more quickly and with much less capital by relying on other people’s vehicles. It could also allow Zipcar to enter rural markets that were previously not viable for its business model — and to do so while taking a cut of rental fees for vehicles it doesn’t even own.

The arrangement could also benefit Wheelz. Building a marketplace doesn’t do much good if nobody uses it, and Wheelz has plenty of competition. Zipcar’s cash and brand could help it beat similar services to new areas.

Zipcar has only announced that it will fund Wheelz, not that it will somehow incorporate its peer-to-peer model under its own brand. But we wouldn’t be surprised if Griffith’s suggestion of the transaction indicating a “first step” in “potentially” offering new services eventually becomes more concrete.

More About: cars, peer-to-peer marketplace, Wheelz, zipcar

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