You love buying your shirts when they go on sale. And who can resist a buy-one-get-one-free offer? So when our stocks go on sale, why do we bemoan their low prices?

Smart investors like Warren Buffett or Marty Whitman love it when their stocks are suddenly selling at bargain-basement prices. For them, these companies become no-brainer buys.

The investors who populate the Motley Fool CAPS community also like a bargain, apparently. Below, you'll find five stocks whose shares are selling at least 50% below their 52-week highs, but which still earn top five-star honors from our investor-intelligence database. Consider it a BOGO sale on stocks.

Stock

CAPS Rating
(out of 5)

% Off
52-Week High

Arch Coal (NYSE:ACI)

*****

69%

ATP Oil & Gas (NASDAQ:ATPG)

*****

61%

Focus Media (NASDAQ:FMCN)

*****

73%

Manitowoc (NASDAQ:MTW)

*****

74%

Mechel (NYSE:MTL)

*****

59%


Naturally, we want you to look a bit closer at these stocks before buying. You can get low-priced appliances in the dent-and-ding section of your home-remodeling superstore, but their quality might not be so good. Same thing here: Make sure there's nothing seriously wrong with the company before you plug it into your portfolio.

Take two, they're small
Crude oil prices broke through the $74 barrier last week, the first time since last October they've done so. Assuming the recovery keeps moving forward -- a very large assumption indeed considering that unemployment, housing, and earnings all remain fragile -- the potential for $100 oil seems great.

Despite reporting a sharp drop in revenue from last year, ATP Oil & Gas had a narrower loss of $0.12 per share than the $0.33 per share of a year ago, as commodity prices and production fell. The partial sale of North Sea and Gulf of Mexico properties contributed to the decline in production, but with an estimated 193 million barrels of oil equivalent in proved and probable reserves, ATP's PV-10 (see next paragraph) was $5.3 billion based on pricing in effect at the end of June. That's a 43% increase in value since December, when oil averaged $68 a barrel and natural gas was $6.18 per million cubic feet. In the most recent quarter, oil was almost $59 and gas was $4 per Mcf.

PV-10 is a rather arcane calculation employed by oil and gas companies to estimate future gross revenue to be generated from the production of proved reserves, minus the costs associated with production and future development. It's then discounted at a 10% rate. It is a formula highly dependent on the price inputs of oil and gas, which is why $100 oil is an important point for ATP. Even at significantly lower energy prices, ATP was able to increase the value of its estimated future cash flows. At higher prices, as seems likely, the E&P concern ought to become a more valuable entity.

That's why CAPS member pehchan finds ATP to be a good investment, though if economic concerns do play havoc with its chances, investors would be wise to keep their eyes on macroeconomic events. "ATPG is a strong company, but just got beaten up too much by recession and oil and recovery worries," wrote pehchan early this month.

Read all about it
Internet portal SINA (NASDAQ:SINA) might back out of a deal to acquire Chinese advertising leader Focus Media if the government doesn't sign off on the deal soon. With pressure against the deal coming from the two state-run media operations, China Central Television and Shanghai Media Group, the likelihood negotiations will be extended beyond the Sept. 30 deadline seem remote.

Focus Media provides advertisers with hundreds of thousands of customized LCD displays, poster frames, and outdoor billboards in shopping malls, elevators, and hospitals across dozens of Chinese cities. It is one of the largest out-of-home advertisers, meaning it dominates the ad market designed to reach consumers when they're away from home. It has only a few smaller competitors, like VisionChina Media (NASDAQ:VISN) challenging it, and several advertising markets where no one has a commanding lead, such as mobile TV advertising, where local government dominates.

The CAPS community remains bullish on Focus Media, with 97% of those rating the media giant betting on it to outperform the market. Yet it has fallen significantly behind the CAPS Media sector as a whole, which advanced 33% over the past month. More than 200 companies comprise the China sector, and their average stock has improved 5%, compared with Focus Media's 3% rise in the same time period.

Have half a mind
It pays to start your own research on these stocks on Motley Fool CAPS. Read a company's financial reports, scrutinize key data and charts, and examine the comments your fellow investors have made -- all from a stock's CAPS page.

Sign up today for the completely free service, and tell us whether these stocks are twice as good at half the price.