Traditional investments are delivering low returns, and home prices are at bargain levels. Is it time to consider buying some rental housing?

Investing in real estate right now can be surprisingly profitable, if everything goes well. Rents are climbing in many areas, and more properties may be coming on the market. Last month, the Obama administration asked for proposals on how to convert at least some of Fannie Mae's and Freddie Mac's bulging inventories of foreclosed homes into affordable rentals.

Investors used to aim for rents that were 1% of the purchase price, or $1,000 a month for a $100,000 home—an annual gross return of 12%—says Michael McCreary. His firm, McCreary Realty, manages about 300 properties in the Atlanta area. Today, he says, some of his investors are getting as much as 2% of the purchase price.

In general, though, average returns after expenses are far less, more like 5% to 6% of the property value, says Ingo Winzer, president of Local Market Monitor, a real-estate forecasting firm. But that still is well above what many other investments yield.