I have a problem with the fact that I have to sign up and PAY before I actually see anything. I don't see it as a huge business the way you describe it. Sorry.
However... what about this twist. Why not get a mailing list started with the theme being a club.... and every month (week, day, whatever) you release a product at a crazy price! Blast out a message.... and show your list how they can take advantage of that deal. In other words... here's a product. It sells for $XX. As a club member... they have a discount coupon to purchase it for $XX which is a discount. That way... you get ALL the orders for that product all at once.
The downside to this model is that if you're selling something that I don't want... you don't get sales. We used to call that the 'special of the month' club.. .where a vendor only makes sales because of his low, low price on that one item. If I don't want that one item... you have no sales.
But the concept is that I become a member of your site for free. I would want to join so that I can take advantage of your specials and savings. You launch a product for (let's say) a week and give your list a coupon code to get that one product at a special price. You process all the orders at once... maybe get a discount because of some volume (from your suppliers) and fill all the orders. As long as you deliver and deliver the quality you proclaim, people will continue to purchase.
Hope this helps! Good luck!