Goal: most money at the end (cash + stocks sold at final prices).
Your turn: ① select a card ② buy/sell any stocks ③ play the card ④ buy/sell again ⑤ end turn.
Key Rule: bought a stock and your card raises it → can't sell it this turn. Sold a stock and your card lowers it → can't buy it back this turn.
Above 250: price fixed at 250; every share pays the excess as cash dividend.
Below 10: price fixed at 10; pay 20 per share or forfeit them. No money and no stock left → you're out.
Last card: the final player may not buy on their last turn. Then everything is sold at the final prices.