Buyers are buying smaller homes, but they want to be able to use and reuse every inch of space, Phipps says. "They are being much more strategic and efficient with how they use it."

Formal spaces that might only be used three or four times per year are disappearing. "The slipcover rooms are gone," says Phipps.

That's "led to a repurposing of space," he says. Formal living rooms have been added to great rooms or converted into home offices or entertainment rooms.

"Three to five years ago, if they could get a loan that would get them into a McMansion with stone and tile and brick and more rooms than they needed, they would do it," says Jeff Wiren, president of the Portland Metropolitan Association of Realtors. "Now they're saying 'I don't know if I want to heat that place and clean it.' They're being much more realistic."