I love nothing better than finding a company that pours buckets of cash into my portfolio. Private-equity funds do, too, but often the cash they're angling for is yours. They love to make public companies into their own ATMs through a shrewd device that you should beware of, and their plundering of companies offers a key lesson for investors like us.

Like an ATM, but better
One legendary private equity shop, Kohlberg Kravis Roberts (NYSE: KKR), has perfected the ability to extract exorbitant sums of cash from companies in a perfectly legal way. Take a look at the recent stunt that it and other big financiers pulled on Dollar General (NYSE: DG). It's the same kind of move pulled by rival private-equity firm Blackstone (NYSE: BX) during bull markets.

KKR and fellow investors Citigroup and Goldman Sachs (NYSE: GS) took Dollar General private in July 2007 at a cost of $7.3 billion. They released the company back to the public markets this past November, offering about 10% of the shares in an IPO and retaining the rest. Also cashing out their share of the underwriting profits were Bank of America (NYSE: BAC) and JPMorgan Chase (NYSE: JPM). Investment banking comprises an exorbitant share of these big banks' revenue and profit.

Company

Investment Banking Revenue 2009

Investment Banking as % of Revenue 2009

Investment Banking as % of Operating Profit 2009

JPMorgan Chase

$25.8 billion

38%

65%

Bank of America (Global Markets segment)

$20.2 billion

28%

180%*

Goldman Sachs

$4.8 billion

11%

6%

Morgan Stanley

$12.8 billion

55%

115%**

Source: Capital IQ, a division of Standard & Poor's.
*Bank of America's operating profit for this division well exceeded its total operating profit, i.e., its other segments lost money in aggregate.
** Morgan Stanley's operating profit for this division well exceeded its total operations profit, i.e., its other segments lost money in aggregate.

Following its launch, Dollar General was valued at $7.2 billion. Now, it looks like Dollar General's investors lost $100 million on the deal, so where's all this profit I'm talking about?

For that, you have to examine how Dollar General was used while it was private. When KKR bought Dollar General in 2007, it and fellow investors put up just $2.8 billion and borrowed the remaining $4.5 billion. At that time, Dollar General had just $260 million in debt, the interest on which it could easily cover with its earnings.

Fast-forward to November 2009 and the IPO. Dollar General suddenly had about $4.2 billion in debt, and its ability to support its own debt was severely crimped. In fact, in its first quarter as a public company, it had to pay about 39% of its operating income just in interest. Ouch!

That sudden debt spike shows that KKR and its co-investors simply transferred their borrowings of $4.5 billion onto Dollar General's balance sheet. For their efforts, they took home a 150% paper profit (based on the IPO price), excluding fees and the costs of some rather minimal work they performed in reorganizing Dollar General -- much of which was charged to Dollar General.

As a final kick to the curb, just before making it a public company, the private-equity giant paid itself and other investors a fat dividend, to the tune of $239 million -- more than double what Dollar General earned in that quarter. As a public company, Dollar General doesn't even pay a dividend. And that's not the amazing part.

The amazing part
Bloomberg quoted one analyst as saying of the IPO, "It's a good price for investors." If by investors, he means KKR and its cronies, then this analyst is spot-on. But for individual investors like you and me, the deal is an awful mess.

What is utterly astounding, mystifying, and discombobulating about this whole process is that investors buy what KKR is selling. After all, no one's under duress to buy a second-tier retailer, and you could even more easily pick up shares in slow-growing cash cows such as Johnson & Johnson or Coca-Cola and be none the worse off. Each has a stellar track record, a stable and growing dividend, and a good consumer-based franchise that should endure well into the future.

So, again, why buy Dollar General? If you must have a retailer, there are quite a few financially sound organizations with good competitive advantages available at cheaper prices. Certainly that's one reason super-investor Warren Buffett recently bought shares of Wal-Mart (NYSE: WMT) instead of the latest IPO peddled by private-equity firms.

The key lesson: Beware not only what you buy, but from whom you buy.

When Dollar General hit the markets again, it sported a 26.9 price-to-earnings ratio -- a stunning 77% higher than that of Wal-Mart, the world's biggest retailer. Even after it reported substantially increased quarterly income, Dollar General still trades at more than 21 times earnings, still much higher than the well-heeled Wal-Mart, which has a more defensible retail position and brand. That price is expensive for such a leveraged deep discounter like Dollar General, especially one poised to lose its attractiveness as we pull out of our economic slump and customers return to full-price retailers and "plain old discounters" like Wal-Mart.

It's little surprise that KKR waited until November 2009 to unleash Dollar General. After all, private equity sells when it estimates the market is highest, and KKR is a private-equity leader for just that very reason. And the unattractive position of Dollar General likely explains why KKR did not spin out the entire company: Investors simply wouldn't stomach this stinky investment in one gulp. But there are still plenty of cheap, undiscovered companies.

Whither my investment dollars?
Rather than invest in discounters teetering on the brink, stick to cash-rich companies that are well-positioned to ride global growth. Focus on the best of the best, the way Motley Fool Million Dollar Portfolio does.

We consistently search for and select from the strongest companies around – small, mid, or large caps -- and invest the Fool's own money in them. Our experts can add the super-power punch of investing to your portfolio, and we even tell you when to buy and sell (always before us).

If you realize that now, more than ever, is the time to own stocks in solid companies, consider joining us at Million Dollar Portfolio. If you'd rather see which companies have already made the cut, simply click here to enter your email address and learn more.

This article was originally published Jan. 29, 2010. It has been updated.

True to its name, The Motley Fool is made up of a motley assortment of writers and analysts, each with a unique perspective; sometimes we agree, sometimes we disagree, but we all believe in the power of learning from each other through our Foolish community.

Jim Royal, Ph.D. , owns shares in Bank of America. Coca-Cola and Wal-Mart are Inside Value picks. Johnson & Johnson and Coca-Cola are Income Investor picks. Motley Fool Options has recommended a diagonal call position on Johnson & Johnson. The Fool owns shares of Coca-Cola, Johnson & Johnson, and Wal-Mart. The Motley Fool has a disclosure policy.