With update 3.15.7.0 rejoice for we can lock cars now guys, default key is O atm, i cant tell if its locked because i only tested it in single player. other players cant steal it if they dont have the item called "stealy wheely automobily"
i've got good news and bad news bad news: this "stealy wheely automobily" can be found in the simplest of places, no need to go too far to get it good news: once the person uses it, it disappears (1 time use to unlock a car)