[PrawkC]

pawn Код:

new MyCars[5];
//Example
public OnGameModeInit()
{
    MyCars[0] = CreateVehicle;
    MyCars[1] = CreateVehicle;
    Etc
    
    return 1;
}

public OnPlayerStateChange(playerid, newstate, oldstate)
{
    if(newstate == PLAYER_STATE_DRIVER)
    {
        new vid = GetPlayerVehicleID(playerid), name[MAX_PLAYER_NAME];
        GetPlayerName(playerid, name, sizeof(name));
        for(new i = 0; i < sizeof(MyCars); i++)
        {
            if(vid == MyCars[i])
            {
                if(strcmp(name, "YourName", true))
                {
                    RemovePlayerFromVehicle(playerid);
                    SendClientMessage(playerid, -1, "Only YourName can enter this car!");
                    return 1;
                }
            }
        }
    }
    return 1;
}

That should work, untested though.

Keep in mind its an example though, like no cars are being created