Owned vehicles are equipped with AI that allows V to summon them in seconds from almost anywhere. If an owned vehicle is ever destroyed, V can summon a replacement, but will be automatically charged €$100  by the insurance company.
V can steal vehicles, but stolen vehicles cannot be permanently owned and will despawn. Cars are more expensive or harder to steal based on their class (Lower, Middle, Upper) and manufacturer. The Body requirement to steal an occupied car ranges from 4-10 and the Technical Ability requirement to break into a parked car ranges from 4-10.
Owned vehicles have a storage space in their trunk (note that some cars are rear-engined, so their storage is located in the front), which is separate from the storage in V's apartment. Motorcycles also have a storage accessed on the rear side of the bike, but it is not shared with cars nor apartments.
Vehicles also perform differently on streets and off-road. A street vehicle with front-wheel drive is typically faster on roads than an off-road vehicle with four-wheel drive, but has very little traction off-road.
It was intended for V to be able to obtain a Yaiba Kusanagi "Mizuchi", which can still be acquired using mods. It's unknown if it's possible to get it through normal means, as the bike has not been found. So far, only Tyger Claws are seen owning this version.
The speed shown on the speedometer is neither mph nor kph, but closer to mph×2, so driving the Rayfield Caliburn at top speed is around 100mph or 160kmh.
It is possible to access all of the passengers seats in the majority of cars, but this feature is probably not intended as of yet, as some animations are not finished (e.g. Herrera GTS back door entrance animation). This can only be done with parked cars which you have to force the door to access them. Then, after exiting the vehicle again, you'll be able to get inside using the other doors. Cars which have suicide doors will instead open as standard doors.
Cyberpunk 2077 — Rides of the Dark Future
Cyberpunk 2077 — Behind the Scenes- Revving Up Night City
Cyberpunk 2077 — Behind the Scenes- Arch Motorcycle with Keanu Reeves and Gard Hollinger