hey GIO, you can sell a security prior to the settlement date; but your broker won't like it and you may get flagged or even have a hold put on your account keeping you from buying more securities. you're best off waiting until the settlement date before executing any trades.
PS: intel is a good pick up, if you're on a round lot, try selling a call if you think it's going down; you can take the revenue from that and invest it immediately
you need to make your brokerage account a margin account. you can't buy the pennies on margin, but you can buy them in a margin account which gets around settlement dates. you can buy and sell in a minute if you like.
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