The average list price is an average of ALL homes available for sale, including ones where the seller is not realistic about their home value. A better comparison is the average list price of "pending" home sales. These are homes which a buyer and seller were able to come to sales terms for. One could reasonably assume that this average list price is a better indicator of a price that the market feels is close to actual value. An appraiser will look at homes that have recently sold, not taking into account what is on the market, in order to determine the best estimated value of a home. It is important when calculating a median sales price to only use comparable properties that have sold in a recent period of time.
Here's an example:
In one neighborhood there are 2 homes under contract priced at $279,900 and $258,000, representing an average price per square foot of $104. However, there are an additional 7 homes for sale, with an average list price of $282,000 and an average price per square foot of $116 (more than a 10% difference). The median sales price for the neighborhood in the past 3 months is $263,000, or $102 per square foot. As you can see, the homes that are priced closer to market value are selling. The homes that are priced well above market value will eventually either expire, be withdrawn, or be reduced to a price that is attractive to buyers.
I hope this helps.
Helen Adams Realty