The auction was conducted by Wayne McDonagh and attracted a large audience because of the profile of the property, Mr Scott said.
"Five people registered interest, but there was strong bidding from two," Mr Scott said.
"Going to auction takes all the backdoor stuff out; it's a very upfront process.
"I think if we'd tendered we wouldn't have got that strong competition, so it was the right decision."
The farm has been running 6200 stock units with the use of a run-off, so the sale property is between 5600 and 5800 stock units. "That's more than $1100 a stock unit; I hate to say 'record-breaking', but it's up there," said Mr Scott.
Mr Scott said the property is prime for location, just 15km from Carterton, and also has good contour and good soils.
"Those are the three unchangeables; you can always change houses, fertiliser or fences," Mr Scott said.
"It was very good for all those attributes."
The property with one-third flat and the rest "medium to steep", and includes two three-bedroom houses -- one of which was built in the late 1800s.
Mahinui has been run as a sheep and beef farm and a breeding property, featuring coopworth sheep and shorthorn cross cattle, the latter being "always in strong demand" when sold as weaners, Mr Scott said.
He said the property has been very traditionally farmed for the past six generations, and it has "lots of potential" for further development, such as regrassing and cropping.
Mr Scott said sheep and beef properties are currently in demand -- if agents can secure them -- with plenty of interest including from the South Island.
"Good-sized units are few and far between -- good-sized economic units," Mr Scott said.