The CIO advises taking a practical and realistic approach to developing these kinds of systems. "Everyone goes into this thinking their data is clean," she says, laughing. "We were pulling data from 40 different data sources. We went into this way overconfident."

Apartment Investment and Management Co. (Aimco), a Denver-based company that owns and manages 240,000 apartment units, hired PROS Revenue Management to develop a pricing and revenue management system similar to those used by hotels and airlines. Lee Montgomery, vice president for revenue management and analytics at Aimco, says the idea was to move beyond "guessing -- spinning around three times and saying, 'I think I'll charge this today.' "

He says these kinds of systems typically increase revenue, but not costs, by 2 percent to 4 percent per year. Three percent for Aimco would be $20 million to $30 million, Montgomery says. "The payback is off the charts," he says.

"And we understand a lot more about our business now," he adds. "It's sort of the 'Aha!' that everybody has. We've seen things we've never seen before, and it's our own data."

For example, these insights have enabled Aimco to increase profits by varying price quotes depending on the time of year a tenant says he wants to rent, rather than quoting a single rate, just as a hotel might have different rates for different seasons and days of the week.