Cheap stocks can get cheaper. They often do.

Unfortunately, "cheap" is a relative term. Precious few stocks that trade for low price-to-earnings ratios or below book value are real bargains. They look enticing, but instead, they're value traps -- stocks that deserve the multiples for which they trade, and punish the garbage-grabbers who buy them.

But don't take my word for it. Here are five "cheap" stocks that trapped bargain-hunting prey:

Company

CAPS Stars (out of 5)

2004 Price-to-Book Ratio

Return Since

KeyCorp (NYSE:KEY)

**

1.96

(79.4%)

Ford Motor (NYSE:F)

**

1.77

(39.8%)

Freddie Mac (NYSE:FRE)

*

1.71

(97.8%)

Redwood Trust (NYSE:RWT)

*

1.71

(57.1%)

D.R. Horton (NYSE; DHI)

*

1.93

(44.0%)

Sources: Motley Fool CAPS, Capital IQ, Yahoo! Finance.

Watch out!
How can you avoid value traps like these? My favorite method is borrowed from professor Aswath Damodaran. In his book Investment Fables, Damodaran counsels investors to measure low price-to-book stocks by their returns on equity (ROE).

Makes sense to me. Book value is shorthand for equity. A low price-to-book stock is priced as if management won't produce high returns from the equity capital afforded it. Find a stock that defies this maxim -- a stock with an above-average and rising ROE -- and you may have found a bargain.

A machete for when you're in the weeds
Our 140,000-member-strong Motley Fool CAPS database is a great place to start your search. I ran a screen for well-respected stocks trading for less than twice book value, and whose returns on equity were 10% or more. Qualifiers were also trading no more than 25% above their 52-week low, leaving plenty of room for further gains.

Of the 37 stocks that CAPS found hiding in the weeds, Florida utility FPL Group (NYSE:FPL) intrigues me this week. The details:

Metric

FPL Group

Recent price

$50.09

CAPS stars (out of 5)

*****

Total ratings

964

Percent bulls

96.8%

Percent bears

3.2%

Price-to-book

1.68

ROE

15.6%

% Above 52-week low

20.8%

Sources: CAPS, Yahoo! Finance.
Data current as of Oct. 29.

Utilities aren't typically where you'll find sexy growth. Yet few stock market stories are sexier than clean energy, and FPL has found a page within the narrative.

"I like FPL as a long-term bet on alternative energy," wrote CAPS investor GonzoDeluxe recently. "They are a traditional utility company, so they will benefit from the shift as motor vehicles move into hybrid and battery powered tech, plus they are moving aggressively into wind power and some solar. They could also benefit from their experience with nuclear power as new nuclear permits start to pick up again."

Also, at 10 times earnings, FPL trades for a discount to other regional utilities, such as Southern Company (NYSE:SO). Mix in a healthy 3.8% dividend yield, and you've got a potential winner in the making.

But that's my take. What would you do? Would you buy shares of FPL Group at today's prices? Let us know by signing up for CAPS today. It's 100% free to participate.

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