step 1: you must create a sense of scarcity - shells will sell much better if the people think they're rare you see, bear with me, take as many shells as you can find and hide 'em on an island, stockpile 'em high until they're rarer then a diamond
she sells sea shell on the seashore but the value of these shells will fall. due to the laws of supply and demand noone wants to buy shells cause theres loads on the sand
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