Well if you want to level your skills at the same time, you could mine 1k iron ore, then buy 2k coal for a maximum of 180 per coal. Then you could smelt them into steel bars and sell them for 550each or more, giving you a profit of at least 190k. Although, there are other methods like merchanting, I would recommend this because you also gain xp. (Or you could just go for the smithing xp and buy everything for a total of 460 per steel bar)