The 'Pandora' property that was owned and run by the late Mathew Dunbar, was sold for $4.65 million at auction last Thursday, well above expectations.

Mr Dunbar was allegedly murdered at the property off the Thunderbolts Way by his de-facto, Natasha Beth Darcy, who remains in custody ahead of a NSW Supreme Court trial later this year.

More than 50 people went to the property auction, held at Walcha Vets Supplies, including Mr Dunbar's mother, Janet Dunbar, who appeared visibly upset by the sale.

Landmark Boulton's conducted the sale of the 479-hectare property on behalf of the vendor, Lance Partridge, as the executor of the estate of Mr Dunbar.

"There was always going to be a lot of interest in the property," Landmark's Bruce Rutherford said.

The property had been in the Dunbar family for three generations, and all eight registered bidders were local residents.

However, only two registered bidders battled it out to purchase the farm that is 13km out of town.

Neighbour Daniel Kermode made the initial bid of $3.5 million before the other bidder, a joint registration by another two neighbours - Henry King and Angus Monie - joined in.

The bidding went back and forth before Pandora was ultimately sold to Mr King and Mr Monie for close to $4,000 an acre.

Mr Rutherford said the number of people in attendance was above average for an auction.

"It was good to see so many local people here," he said.

"It's a beautiful parcel of country, in a wonderful part of the district, but I didn't see it making this much - it is a very good price."

Australian Community Media understands the proceeds from the farm sale will be held in the estate until the completion of Darcy's trial.

Mr Dunbar's body was found on on the property in the early hours of August 2, 2017. His death was treated as suspicious.

After an investigation by Oxley police, Darcy was arrested in Walcha in November 2017 - three months after Mr Dunbar's death - and charged with the 42-year-old's murder. She has been behind bars since.