public OnPlayerStateChange(playerid,newstate,oldstate)
{
if(IsPlayerInVehicle(playerid, 462))
    {
        if(newstate == 2)//checks if player entered as driver
        {
            if(GetPlayerMoney(playerid) >= 25) //25 = the money u want the car to cost.
            {
                GivePlayerMoney(playerid,-25);
                SendClientMessage(playerid,0xFFFF00AA,"You just bought this car.");
            }
            else
            SendClientMessage(playerid,0xFFFF00AA,"You don't have enought money for this car.");
            RemovePlayerFromVehicle(playerid);
        }
        else
        SendClientMessage(playerid,0xFFFF00AA,"You need to enter as driver to buy this car."); //change YOUR_COLOR to the colors you have got and that you want to use
        RemovePlayerFromVehicle(playerid);
    }
}