Rich Arzaga owns a luxury home in San Ramon, California, but he's not betting on it as an investment. The founder and CEO of Cornerstone Wealth Management, who bought the 5,000 sq. ft. property in 2005 for $1.8 million and has spent $500,000 improving it, considers the abode a wonderful place for his family. But ask him to rate his home -- or any home, for that matter -- as a financial investment, and Arzaga balks. "It's the American Dream to own a home, but whoever said that didn't do the analysis on it," says Arzaga, knowing he's taking a...