WSJ story on RealEstate Mania

WSJ.com - As Prices Rise, Homeowners Go Deep in Debt to Buy Real Estate:

Economists Say Move to Tap
Equity May Inflate Bubble;
Like Buying on Margin

"Those rapid profits reflect surging house prices, rising at a double-digit rate in the Epsteins' area near Washington. "It's a wonderful market out there," Mr. Epstein says.

Five years into a housing boom that has boosted U.S. home values an average of 50% and added an estimated $5.5 trillion to the total market value of residential real estate, many Americans no longer think of their home as just a place to live. Instead, it's a cash machine that can be used to rapidly build wealth. To that end, a growing number of people are tapping into their home equity to invest in more real estate.

That's a lot like using a margin account -- a line of credit backed by securities in an investor's portfolio -- to buy stocks. During the 1990s, many investors used such accounts to buy shares in fast-rising tech stocks. When the dot-com bubble burst, the value of the shares bought on credit cratered and investors' borrowing worsened their losses. Economists say today's debt-fueled investment binge in real estate is fanning the flames of an already overheated housing market, and making demand from people who actually need houses to live in seem stronger than it truly is.

In some markets, this buying is adding to a glut of rental housing and causing rents to fall, which will make.ENAmore difficult for investors to break even. Already, there are signs that a few investors are starting to get burned."

and

"In another sign of growing concern, the Federal Reserve and other bank regulators last week issued guidelines calling for lenders to tighten their criteria for making loans backed by home equity by looking more closely at borrowers' ability to repay under various possible future market conditions. The regulators are starting work on similar guidelines covering mortgage loans used to purchase homes. Among regulators' top concerns: the surge in popularity of interest-only loans, which allow people to pay only interest in the initial years and face the burden of paying back the principal later."