Foreclosure starts increased in 18 states in August, as 99,405 properties began the foreclosure process last month, according to information released this week by RealtyTrac. That's a 1% increase from July, but a 13% decrease from last August, when foreclosure starts hit a 17-month high.

In total, RealtyTrac reported foreclosure filings -- default notices, scheduled auctions, and bank repossessions -- on 193,508 U.S. properties in August, down 15% from August 2011. Illinois posted the nation's highest foreclosure rate, according to RealtyTrac.

Interestingly, RealtyTrac noted a split between so-called judicial states, where the courts need to approve foreclosures, and the nonjudicial states. Judicial states including Florida and New York saw increases, while nonjudicial states including Arizona and California saw a downward trend.  

Investors in companies like Caterpillar, Lowe's, Home Depot, and Lumber Liquidators will want to keep an eye on trends in both residential and commercial real estate, as shares in these businesses are considered plays on a large-scale housing recovery.

Longer-term investors in these four stocks are probably looking for more of the same returns they've enjoyed in the past year. Despite sluggish macroeconomic growth, shares in these four companies rose nearly 90% as a group in the past 12 months.

Fool contributor John Divine owns none of the stocks mentioned in the story above. You can follow him on Twitter @divinebizkid and on Motley Fool CAPS @TMFDivine.

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