public Packet sell(int id, int slot)
    {
        int price = item.getSell(id);
        if (price == -1 || !itemAtSlot(id,slot)) {
            return getErrorPacket(noitem,0xEB);
        }
        bot.setGigas(bot.getGigas()+price);
        bot.setInvent(0, slot);
        return bot.getInventPacket(head_sell);
    }