Final answer:
When buying stocks in a margin account, the customer has to pay at least the initial margin requirement.
Step-by-step explanation:
When buying stocks in a margin account, the customer has to pay at least the initial margin requirement. The initial margin requirement is the minimum percentage of the total value of the stock that the customer must pay upfront in cash or eligible securities. This is typically set by the brokerage firm and serves as a form of collateral.
For example, if the initial margin requirement is 50%, and the customer wants to buy $10,000 worth of stocks, they would have to pay at least $5,000 as the initial margin.