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, apparently. Below, you'll find three companies whose shares are selling at least 50% below their 52-week highs but that still earn high honors from our investor-intelligence database. Consider it a BOGO sale on stocks.

Stock

CAPS Rating (out of 5)

% Off  12-Month High

Alvarion (Nasdaq: ALVR)

****

55%

Duoyuan Global Water (NYSE: DGW)

****

77%

Trident Microsystems (Nasdaq: TRID)

****

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 in to your portfolio.

Take two; they're small
Investors in Alvarion maintain their own upbeat opinions, despite the so-called death of WiMAX. More than 1,000 CAPS members have weighed in on the wireless broadband systems provider, and 97% say that Alvarion still has the chance to be a monster stock.

But how much longer can Alvarion hang on? Sprint Nextel (NYSE: S) introduced the first 4G 3-D smartphone (no special glasses required!), but after AT&T (NYSE: T) moved to gobble up T-Mobile, the market has a pretty dim view of Sprint's own prospects. A year ago, Sprint unveiled the first WiMax phone, and while its new version is also WiMax-capable, the previous version didn't do much to help the industry.

Alvarion said last month that it was going hack away at employee counts and restructure the company in the face of continuing losses. Even if it's able to turn a profit -- and as one analyst notes, cut enough personnel and it will be profitable -- what sort of revenues will it be able to generate?

Add the WiMax specialist to the Fool's free portfolio tracker and keep tabs on whether Alvarion is able to survive the adoption of rival LTE technology.

A reserve player
There's a stench hanging over Chinese small-cap wastewater-treatment stocks, and it's not from the sewage they're filtering. RINO International, China Valve Technology (Nasdaq: CVVT), and Duoyuan Global Water have cast a pall over water-conservation companies in the country because of financial shenanigans, but in the case of Duoyuan, it's guilt by association because of actions taken by a wayward printing affiliate. The excess of bearish views suggests that where there's smoke at one company, there's bound to be fire at the others.

Despite a 14% increase in revenues for Duoyuan Global that generated a 21% jump in profits, the results missed analyst expectations and the company had to delay yet again the startup of a new manufacturing facility until sometime in the third quarter. The company had originally planned on opening the facility in the first quarter of 2011, but that's been pushed back and Duoyuan needs to commit even more resources to the project.

It's also undergoing an accounting review, and that's going to be extended out further than analysts anticipated, to the end of the second quarter. So even though there's a growing need for wastewater treatment and conservation plants in China as its economy rapidly expands, investors need to keep a close eye on individual developments. Yet it's that need that has CAPS member prophetofprofit7 seeing beyond the latest issues.

Revenue and net income is steadily rising both annually and quarterly. Furthermore, away from the fundamentals water is a hot topic of discussion internationally and there is a lot of upside to this company being in China who needs clean drinking water for a billion and change Chinese. In addition to this being a good play on water demand DGW is [an] emerging market play obviously because of China.

Let us know in the comments section below or on the Duoyuan Global Water CAPS page whether this stock will flood investors with profits.

Familiarity not breeding contempt here
Don't expect much out of Trident Microsystems' first-quarter earnings report when it releases results in May. Best Buy (NYSE: BBY) reported a poor first quarter, and if it runs true to form, Trident will follow with a dour note as well, because TV sales in particular and consumer electronics generally still haven't gained traction with shoppers.

Last December, the big-box electronics retailer shocked everyone with a really dismal assessment of sales just before Christmas, and integrated-circuit maker Trident came through with a pessimistic report in February that also dampened enthusiasm for the first quarter. (That could have been a hint Best Buy was still going to be in trouble.) Now Best Buy's numbers are out again, and while the company has thrown a lot of different changes into the mix -- closing down stores in China and Turkey, for example -- sales of consumer electronics, stuff for which Trident makes the chips, haven't been very good either. So don't look for a rebound just yet.

But the sector will come back eventually, and as the newer technologies such as 3-D and Internet-ready TVs gain more of a toehold, we'll see more sales there, too. CAPS All-Star members see a recovery coming eventually, as 98% of those rating the chipmaker believe it will outperform the broad market averages. You can watch the turnaround by adding Trident to your watchlist.

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

Best Buy is a recommendation of Motley Fool Inside Value and Motley Fool Stock Advisor. The Fool owns shares of Best Buy. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.

Fool contributor Rich Duprey owns shares of Best Buy but has no financial position in any of the other stocks mentioned in this article. You can see his holdings. The Motley Fool has a disclosure policy.