A "one-of-a-kind" Austin property set on a bluff overlooking Barton Springs Road will sell to the highest bidder through an online auction on Oct. 26.

Joe Longton, the Austin real estate agent who has the listing, said he can see the 511 Barton Blvd. property selling to a wealthy buyer — such as a company executive or a movie star for their private residence — or to an office, apartment or condominium developer.

Longton, with Kuper Sotheby’s International Realty, currently has the 2.1 acres listed for $4.5 million. The upcoming sale will be conducted by global auction firm Concierge Auctions.

"It is truly a one-of-a-kind property that you’ll never see again," Longton said. "It has some of the most beautiful views of downtown Austin that can be found anywhere in this city."

The property, which has been in the same family for 83 years, is near Zilker Park.

The Travis Central Appraisal District lists three parcels for 511 Barton Blvd., with a combined appraised value of $3.76 millon. The owners are listed as the June Thorp Rade Marital Trust I and Raymond H. Rade Family Trust of Goliad, Texas. The property has been in the hands of the Thorp and Rade families for decades.

"Impossibly rare and auspiciously positioned, this hidden gem has finally become available after 83 years," Concierge’s website for the auction states.

Raymond D. "Boss" Thorp died in 1975 at age 84. His obiturary said Thorp came to the Austin Police Department in 1924 to set up a fingerprint bureau, was promoted to chief in 1928, and served as the city’s top cop for 30 years.

June Rade, Thorpe’s daughter, and her two sons, Bruce Rade and Brent Rade, own the property in a family trust.

Longton said it was the family’s decision to auction the property "to get maximum exposure" for an expedited sale. Inquiries have come in from all around the U.S. as well as internationally, Concierge executives said.

"Auctions work very well with trophy properties," Longton said. He said Concierge has 40,000 registered bidders worldwide.

The property will sell via Concierge Auctions’ online marketplace, allowing prospective buyers to bid digitally in real time from any continent. The property will be sold to the highest bidder, with the minimum bid set at $1 million. The sale is expected to become final on Jan. 2.

Longton told the American-Statesman that the property is drawing high interest, including from high net-worth individuals; almost a dozen of Austin’s most active apartment developers; and even movie stars.

"I show the property two times a day," Longton said.

A 2,600-square-foot house and garage apartment are currently on the site, which is zoned for general commercial services and offers a variety of options for the new owner, Concierge officials said. Longton said the structures have been deemed to not be historically significant.

Longton said he has met "with at least four parties — some of the most significant names in this city" — who are interested in the site for a private luxury residence.

"It literally is a movie-star property," Langton said. "When I first listed the property, I thought for sure that this was a Matthew McConaughey or Sandra Bullock type of residence. It really lends itself to some type of movie star or signficantly named person in our city or somewhere in the world, a Brad Pitt or any other famous movie star who’s kind of hip."

Longton said the property also could be suited for a low-density office development and/or a high-end apartment or condominium project. Several such luxury residential projects have sprung up in recent years on the north side of Barton Springs Road.