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I've been considering Banco Santander (NYSE: STD) as a potential candidate for my Motley Fool real-money portfolio for about a month now.

In fact, the last time I wrote about the company, I asked readers which bank they'd most like to own: Santander, National Bank of Greece (NYSE: NBG), Allied Irish Banks (NYSE: AIB), or Banco Bilbao Vizcaya. An overwhelming majority (66%) said they'd rather own Santander; since that article, the stock has dropped by more than 5%.

Is it time to buy?
I've been touting the positive attributes of this Spanish banking giant for a long time, so you would think if the stock took a hit -- as it has lately -- that I would be jumping to strike while the iron was hot. And normally, I would. Santander has shown in the past year that it's not afraid to make moves, whether it be an acquisition or retail expansion to steal market share from major competitor Banco Bilbao Vizcaya. Just check out some of the activity in 2010:

  • Santander bought U.K. assets from Royal Bank of Scotland that included 300 retail branches.
  • In June, it bought back about a quarter of its Mexican unit from Bank of America (NYSE: BAC) for $2.5 billion.
  • Around the same time, it bought $3.2 billion of auto loans from Citigroup (NYSE: C).
  • The company has talked with M&T Bank (NYSE: MTB) to explore merging Santander's Sovereign Bank into M&T's retail operations.

And most recently, General Electric (NYSE: GE) announced the disposition of certain Mexican assets to who else but Banco Santander. The company is buying about a $2 billion mortgage portfolio of Mexican real-estate assets from GE's finance division.

All of this is great news, at least in my opinion, for a company that has more than $300 billion in cash on its balance sheet and is constantly scouring the tortured banking landscape for great deals. However, the Spanish housing market is still struggling to stay afloat, as new information emerged last week that shows sales are down 50% since summertime and prices could drop an additional 30%. This would obviously wreak havoc on the books of many banks, and Santander certainly isn't immune to the pain. Its diversified revenue stream will surely help, but Spain continues to be a scary place to invest.

For that reason, I'm still holding off on Santander, but don't be surprised if I pull the trigger should the price continue to decline.

Interested in Banco Santander? Add it to your watchlist to get all the latest news and analysis.

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Jordan DiPIetro owns shares of National Bank of Greece. The Fool owns shares of Bank of America. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.