Blockchain-powered marketplace startup ShareRing, conceived last year by former executives of car-sharing platform Keaz, has announced a service that will let users book and unlock a rental vehicle within 30 seconds.

For its debut, the service is partnering with Keaz to provide a wide selection of rental cars (Keaz works with Toyota, Merchants Fleet Management, Envoy, Yoogo, and others). The Keaz platform currently handles about 70,000 rental bookings per month, but it can take a few days to sign up for the service and gain access to a car. The ShareRing service can verify a new user’s ID and approve a booking almost immediately.

ShareRing expects to expand its service to other car rental companies in the future, and it has efforts underway to handle a range of shareable property that extends beyond cars.

The service will debut March 29 and is set to launch in stages, starting with the U.S. West Coast (CA and NV), Australia, and Hong Kong, before expanding to London.

Integration will be available wherever Keaz-enabled vehicles exist (300 locations across the U.S., Australia, and New Zealand, with the U.K. scheduled during Q2, 2019), but ShareRing could announce other major partners in the coming months.

The company cites several benefits blockchain brings to a sharing marketplace:

Self-sovereign ID can push a fully checked ID to the rental company in a matter of seconds, allowing for instant signup and validation.

can push a fully checked ID to the rental company in a matter of seconds, allowing for instant signup and validation. No additional hardware requirements for existing car-sharing networks. Just add the ShareRing QR code to the windscreen.

requirements for existing car-sharing networks. Just add the ShareRing QR code to the windscreen. No risk of credit card fraud, thanks to the blockchain-based validation process.

thanks to the blockchain-based validation process. Automatic escrow payments/deposits increases efficiency.

increases efficiency. Company-agnostic system can easily integrate with existing rental offerings.

ShareRing has built its own blockchain based on the Tendermint Consensus engine. The team chose not to build the service on a public blockchain because it wanted to keep usage costs low while allowing for a high transaction rate and the scalability to support a large sharing economy, cofounder and CEO Tim Bos told VentureBeat. The chain is powered by a dual currency system — a utility currency, ShareToken, and a stable coin, SharePay, which allows users to pay in their local currency.

Meanwhile, users can control how their ID is managed. For example, Bos explained, “We offer a function where you can choose to only do business with providers that don’t hold onto your ID.”

None of a user’s identifiable information is stored on the ShareRing chain, said Bos. “This is a system where identity documents are captured in the app by the user (license or passport, depending on the category of use) and verified by a third-party Know Your Customer provider. Once authenticated, these documents are hashed and uploaded to [the ShareRing chain]. This hash is an unchangeable ID validator that is used by the business service provider to ensure that it’s valid and the renter is who they claim to be.”

Some aspects of the rental will be stored on the blockchain, he said, such as customer ratings and details on any accidents or damage. “This will allow providers to offer enhanced services, such as tailored insurance. Or perhaps they’ll offer custom pricing based on the user’s reputation.”

ShareRing is registered in Malta and has sales and tech teams in Australia, Vietnam, Hong Kong, and Las Vegas. The company completed an ICO in mid-2018 and has raised the equivalent of about $8 million in Ether.