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 in the Motley Fool CAPS community also like a bargain. Below, you'll find five companies whose shares are selling at least 50% below their 52-week highs, but that still earn top ratings from our investor-intelligence database. Consider it a BOGO sale on stocks.

Stock

CAPS Rating (out of five)

% Off 52-Week High

ConocoPhillips (NYSE:COP)

*****

55%

K-V Pharmaceutical (NYSE:KV-A)

*****

87%

Suncor Energy (NYSE:SU)

*****

53%

Vale (NASDAQ:VALE)

*****

51%

Weatherford International (NYSE:WFT)

*****

60%

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
Sometimes a company's share price is dragged down for no good reason other than investor pessimism about general market conditions, meaning it could be a good time to scoop up shares. Then there's K-V Pharmaceutical, which seemingly deserves its beaten-down price. Its five-star rating is curious.

Things began unraveling last year for the specialty pharmaceutical company after the Food and Drug Administration ordered about 20 companies to stop selling cough medicines that contained time-released guaifenesin. K-V Pharmaceutical ignored the order, and the agency seized $24 million worth of the company's drugs. The company fired its CEO in December, and then all its shipments of FDA-approved drugs in tablet form were suspended.

In March, the Justice Department filed a lawsuit against K-V Pharmaceutical -- not to mention the raft of class action lawsuits against it -- for the significant violations it allegedly committed as well as allegedly continuing to manufacture unapproved drugs. Although the company reached a consent decree with the FDA, agreeing that it will not make any more drugs unless it gets the agency's approval, there's no timetable for when that will happen.

While K-V Pharmaceutical is stuck in limbo, rivals have the opportunity to steal any market share it might have had. For example, Baxter (NYSE:BAX) had to stop selling an eye-wash solution last year because it contained unapproved drugs, giving rival Alcon (NYSE:ACL) a chance to gain on it. K-V Pharmaceutical will look over its shoulder as competition heats up for its pig-based pancreatic enzyme drug, a version of which has been approved for sale by Belgian competitor Solvay. Tiny Altus Pharmaceuticals also makes a competing, though differently formulated, product.

So it's hard to understand why investors find K-V Pharmaceutical attractive. It has cut almost half its workforce, settled a lawsuit with Purdue Pharma about patent infringement involving OxyContin, and received a delisting notice from the New York Stock Exchange for failing to file its annual report. Although the annual report filing might be a formality, until the company completes its internal audit, there's enough drama here to say that buying a stake in it hardly seems prudent. It might just be better to put a stake through it.

CAPS All-Star 30andholding, though, thinks a case can be made for K-V Pharmaceutical's recovery.

They settled a patent infringement lawsuit and are now allowed to sell a generic version of the drug for a year. They have an agreement with the FDA which lays out steps for them to return to production. I think the stock will rebound.

Similarly, actuary99 writes that if the company overcomes obstacles, it could thrive, what with all the bad news being out in the open.

Only risk is bankruptcy. If the FDA mess gets over anytime soon, this one will jump, as it has over the past few days.

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.

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Fool contributor Rich Duprey does not have a financial position in any of the stocks mentioned in this article. You can see his holdings. Test- drive The Motley Fool's disclosure policy.