Veteran Motley Fool Hidden Gems members know what we love to find in a small company. Honest, competent management. Solid financials. High levels of insider ownership. Strong returns on equity and assets. Little or no Wall Street coverage. And a price that's right for long-term buyers.

What we don't often talk about, though, are the things that can go bump in the night -- the nasty traits of some small businesses that make us fear and loathe them.

10,000 and counting
There are more than 10,000 public companies capitalized at less than $500 million. Sure, there are loads of great winners in that bunch, companies that are poised to rise many times in value. Look back, and you'll find businesses such as Guess? (NYSE:GES). Buying this apparel retailer five years ago would have given you an 11-bagger. Now that's a classic Peter Lynch investment.

But let's not kid ourselves. Out of those 10,000 small companies, there are tons of mediocre (and worse) firms. Like Tolkien's terrible dragon, Smaug, they can incinerate your savings in no time. (Hey, we warned you this was scary stuff!) Quite seriously, if you're not doing business research and you don't know what to avoid out there, you could lose your fortune. When even seemingly solid companies such as Jabil Circuit (NYSE:JBL) and Expedia (NASDAQ:EXPE) can drop precipitously from their recent highs (down 33% and 40%, respectively), you have to keep your eyes wide open.

Let's start with an example of what to avoid.

Case study: Charter Communications
In our active online community, a Motley FoolHidden Gems member asked us more than a year ago what we thought of Charter Communications, a broadband cable company whose chairman and largest shareholder is Microsoft co-founder Paul Allen. The business is also substantially owned by Wally Weitz, a Nebraska-based investor greatly admired by Warren Buffett fans, who found great returns in stocks like Apollo Group (NASDAQ:APOL) and WellPoint.

Charter stock had fallen from $25 to $4.50, and our member wanted to know whether it was a good time to get in for a turnaround.

We'll start by saying that at Hidden Gems, we absolutely love the broken small cap that's poised for a turnaround. Show us a company whose stock has fallen 90% from its highs, whose chairman is a billionaire, and whose largest institutional owner is a close friend of Warren Buffett, and we'll sign up to do very careful research. That's exactly what we did with Charter Communications at $4.50.

But we did not like what we found. Here's why (a year ago) we warned against investing in this business:

  • Massive debt. Net debt (debt minus cash) was more than $18 billion.

  • Net debt was 28 times the company's market cap of $640 million.

  • Charter was unprofitable under generally accepted accounting principles, with $1.5 billion in yearly interest costs.

  • Debt covenants posed a serious threat to the company's survival.

  • The Securities and Exchange Commission had launched an investigation into Charter's accounting practices.

  • Heavy spending for cable infrastructure hadn't yielded high enough returns.

Near the end of June 2003, I (Tom here) wrote negatively about this stock when it was trading above $4. It's tough to go contrary to Paul Allen and Wally Weitz, but there was no turnaround in sight, and the company's balance sheet was cratering. Today, Charter has been on a bit of an uptrend, trading at $2.57 per share. That still makes for a more a 35% decline during a period in which the S&P 500 has increased some 38%.

Ouch.

What we do and don't fear
Oddly enough, our Hidden Gems team does not fear high debt in and of itself. Our recommendation Mine Safety Appliances carries more than $45 million in debt, yet the stock has jumped 120% since it was recommended, and we remain optimistic about its future. The company's operations are strong enough to repay those obligations.

Nor do we fear companies that have fallen 90% from their all-time highs. Apple (NASDAQ:AAPL), for instance, is up more than 900% since being hammered when the tech bubble popped a few years back.

What's more, even a hint of unseemly scandal can create attractive bargains on occasion. One of our current recommendations had a CEO step down after some problems, but the stock is up 87% for us. We believe it could be a multibagger in the years to come. Many companies have rebounded nicely from similar setbacks.

Each of these scary factors individually could make for a compelling investment as the stock price drops into the real value range.

So, what was the problem with Charter Communications? The scale of its debt, running north of $18 billion, alongside harsh payment terms and emerging accounting problems. The numbers just didn't add up, and we're still very wary of the stock.

To find out which stocks we do love, simply take a free trial of Hidden Gems. Read about all the small companies that have produced outsized returns for us thus far. If you don't like it, you can cancel within 30 days without paying a dime.

This article was originally published on Jan. 13, 2005. It has been updated.

Tom Gardner and Rex Moore anchor the gold medal-winning Motley Fool 4x100 three-legged sack race relay team. Tom and Rex own shares of Microsoft. Microsoft is an Inside Value recommendation. The Motley Fool has adisclosure policy.