These are the addons the developer of Vehicles has coded.
The WorldGuard Flags Addon, adds a WorldGuard flag for each vehicle (ALLOW or DENY) that allows or denies the placing of certain vehicles in a region. Author: Pollitoyeye Link: https://www.spigotmc.org/resources/vehicles-worldguard-flags.28788/
The PlotSquared Addon, adds different types of protection regarding Vehicles for you to utilize in your Plots world. Author: Pollitoyeye Link: https://www.spigotmc.org/resources/vehicles-plotsquared-protection.74753/
The Vehicles Limiter Addon, adds a limit to how many Vehicles a user can place. Author: Pollitoyeye Link: https://www.mediafire.com/file/53t1oe903btlobo/VehiclesLimiter.jar/file Dependency: https://www.spigotmc.org/resources/bkcommonlib.39590/