This is a game!
1. DECIDE who is wholesaler and who are shop owners.
distribute the first capitals.
2. STOCK some kinds of the merchandise from wholesaler.
different merchandise has different value.
3. PLAY DICE of weather.
different weather result in different selling price.
who's earned , or lost his money? who is the best shop owner !?
You can add some rule ( e.g. 10 coins enable owner to enlarge his shop, or debt system )
ENJOY your market ideas and HOPE good weather comes good timing.