For many investors, banking stocks are more of a headache than they seem to be worth. You've got funny concepts like "efficiency ratios" and "tier one capital," and everybody seems to remember the savings-and-loan fiasco, even if relatively few people can recall what it was all about. And then here we have the case of California's Commercial Capital Bancorp (NASDAQ:CCBI) -- a bank that's a little weird even by bank standards.

To be sure, this is no Citigroup (NYSE:C), Commerce Bancorp (NYSE:CBH), or BB&T (NYSE:BBT). Rather, Commercial Capital is something more of a niche bank, focusing its efforts on income-property investors. It's one of the largest originators of loans for multifamily property in California.

All the same, the fourth quarter was a challenging one. Reported net income dropped 25%, and even adding back costs tied to building up its commercial-banking unit leaves the company a bit shy of the average forecast. For the quarter, net interest income was down almost 3%, while non-interest income fell 9%. And as the increase in cost of funds outstripped the yield on assets, the net interest margin shrank by 17 basis points from last year to 3.21%.

This is a bank story with a fair bit of flux to it. The company is buying another bank (Calnet Business Bank), facing an injunction from Comerica (NYSE:CMA) over some employees that Commercial Capital hired, and operating in the wild and wooly world of the California housing market.

Parts of this bank's story strike me as odd. Now, I understand that management said the bank saw the majority of its asset growth in December, but it looks to me as though average loans increased just 5% and deposits were actually down from the year-ago period. I'll be the first to grant that Commercial Capital is a different sort of bank, but that's still a cause for some concern -- though the sequential growth from the third quarter was pretty promising.

Given the state of housing affordability in California and the influx of population, I think there will be pretty decent demand for new multifamily dwellings -- and, therefore, more loans from Commercial Capital. I also think the valuation on these shares could prove to be very interesting. Still, it's a very different breed of bank, so investors would do well to take extra care with their due diligence before making any investing decisions.

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Fool contributor Stephen Simpson has no financial interest in any stocks mentioned (that means he's neither long nor short the shares).