EDWARDS, Colo. (AP) - Bob and Karin Weber built their dream home 14 years ago, creating an 11,000-square-foot mountaintop oasis. Now that the couple is in their 70s, they're ready to downsize.

EDWARDS, Colo. (AP) Bob and Karin Weber built their dream home 14 years ago, creating an 11,000-square-foot mountaintop oasis. Now that the couple is in their 70s, they're ready to downsize.

The Webers tried the traditional list-and-wait method of selling the 35-acre Elk Ridge Ranch but decided to put their estate up for auction, hoping for a streamlined process and a more lucrative result.

Auctions have become a viable option for selling luxury homes, mirroring marketing techniques for antiques and collectibles.

The National Association of Realtors says properties costing more than $1 million represent about 3 percent of the total housing market.

With sales of luxury homes and prices on the rise, sellers can use an auction to control the structure of the sale, set a firm deadline for the transaction and hope a bidding war will send the price higher.