In one of Nick Szabo’s classic papers on smart contracts he gives an example of smart property:
Smart property might be created by embedding smart contracts in physical objects. These embedded protocols would automatically give control of the keys for operating the property to the party who rightfully owns that property, based on the terms of the contract. For example, a car might be rendered inoperable unless the proper challenge-response protocol is completed with its rightful owner, preventing theft.
Airbnb is close to achieving smart property. On a recent trip, for example, I booked online. Shortly before I was to take control of the residence I received a code which opened an on-site lockbox with a key. I left the key in the lockbox when I left–never having met the owner or any employee. At a hotel that I stayed in on the same trip, I still had to wait in line to check-in. The Airbnb process is more convenient and cheaper because there is no need to have staff to man a front desk.
The Airbnb process typically uses physical keys but I have also stayed at places that use electronic keys and digital door locks. An electronic key is more secure since it can be a one-time use that opens the door only during the rental period.
All of this may seem somewhat ordinary but that is the point. Smart property is becoming ordinary.
Addendum: The more automated the process becomes the more a decentralized protocol or platform becomes a competitive option. Smart property that can reach out to say a matching protocol and an identity protocol could rent itself.
Airbnb is a very good company that provides valuable services at reasonable prices so a decentralized platform may not have significant advantages but as more base protocols are laid down and stabilized (“primitives”) it will become easier and more natural to create these kinds of decentralized services. See my post Blockchains and the Opportunity of the Commons.