I've done some business in EVE Online for a while, and it's as much fun as you describe, but a somewhat more mature market. Any competent EVE trader would have

I've done some business in EVE Online for a while, and it's as much fun as you describe, but a somewhat more mature market. Any competent EVE trader would have squeezed into your market quite easily, and even have a choice of two methods. The "Chinese gold farmer" way is to be in the spaceport all the time and keep outbidding you minimal amounts. At the end of the month, your resource stocks would be bought at the same price, and their quantities proportional to the relative time amounts each of you has spent in the spaceport. So they can sell at the same price as you, or even lower if they value their time less and would accept less profit. The "lazy" way (my favorite) requires very little capital and very little time. The idea is to seriously outbid you but only offer to buy small quantities. You will only be able to match this bidding war up to a limit, since you're paying very inflated prices and buying a hundred times more than I do. (If you miscalculate, you'll end up with a huge stock of finished products that you can only sell profitably at ten times the previous price, and people will simply not buy.) Once you've reached this limit, you have to allow me into the market, and I'm buying and selling at pretty much the same prices as you do.