Complete #1 for Exercise 23 on page 154 of Rhetorical Grammar (our book).
Never be an investor in something you don’t understand or in the dream of an artful salesperson of some product. Be a buyer, not a sellee. Figure out for yourself what you want to buy (be it life insurance, mutual funds or a vacuum cleaner for the home) and then shop for a good buy before making up your mind. Don’t let someone else tell you what the necessities of life are–at least not if he happens to be the salesman who wants to sell it to you.