public int NextId(string type)
        {
            int id = 1;

            if (type == "consumable" || type == "other")
            {
                var items = new ItemDataAccess().FindAll <Item>();
                if (items.Count != 0)
                {
                    id = items.OrderBy(x => x.Id).Last().Id + 1;
                }
            }
            else
            {
                var equipments = new EquipmentDataAccess().FindAll <Equipment>();
                if (equipments.Count != 0)
                {
                    id = equipments.OrderBy(x => x.Id).Last().Id + 1;
                }
            }
            return(id);
        }