Home owners may be increasingly overvaluing their homes. Appraiser opinions of home values were 2.33 percent lower than home owners' estimates in July, according to Quicken Loans' national Home Price Perception Index. The gap between home owner estimates and appraiser opinions were nearly double the gap between the values in May.

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"Many home owners around the country are seeing the national headlines about home value increases and they are optimistic about their equity increasing," says Bob Walters, Quicken Loans chief economist. "While some areas are seeing the same level of home appreciation, or even more, there are also some areas that have slower home value increases. This can lead to home owners and appraisers not quite seeing eye-to-eye."

Home values in a handful of markets mostly stayed flat last month on a month-to-month basis, according to Quicken Loans' HPPI.

"A slowing of home value increases adds to the misunderstanding of local home values," Walters says. "Appraisers are viewing the housing industry every day; they know when home values growth may be slowing. Home owners may think values are still skyrocketing, when they have instead returned to more healthy appreciation in their area."

Source: Quicken Loans