The interesting part is that margin isn’t determined simply by how much you invest. Two stocks worth USD 10,000 can consume very different amounts of buying power because brokers assess factors such as volatility, liquidity, price movements and overall risk.

For example, a stock with a 30% margin requirement would tie up USD 3,000, while another with a 50% requirement would tie up USD 5,000—even though the position values are identical.

And here’s the part margin traders shouldn’t overlook: margin requirements can change. A stock offering high leverage today may require more margin tomorrow if market conditions deteriorate.

So, “up to 4× leverage” should never be interpreted as guaranteed borrowing power. The smarter question is not “How much can I leverage?” but “How much leverage can my account safely handle?”

@Tiger_AU [正经]