The consultants who carried out a due diligence for the Indigenous Land Corporation's controversial purchase of the Ayers Rock Resort received a $3 million commission from the $317 million sale.
But the Abbott government has dismissed the need for a public inquiry into the purchase.
The corporation's new chief executive officer Michael Dillon said the previous board paid between $50 million and $100 million too much.
McGrath Nicol was commissioned to review the assumptions underpinning the sale.
Mr Dillon told the hearing the review found the corporation's board was relying on a property valuation that was 17 months old when it made the acquisition.
The due diligence, which cost more than $6 million, was on a "success-fee basis".
The consultants and Grant Samuel, a corporate advisory group, received one per cent of the purchase price which equated to $3 million.
"That's extraordinary," Liberal senator Zed Seselja told a Senate estimates hearing in Canberra on Friday.
"There's effectively an incentive for the individual or company to value it at a higher rate because they get more of a success fee."
The review also found that capital expenditure projections had been miscalculated and occupancy rate projections had been "overly optimistic" in light of a tourism downturn in the Northern Territory.
Resort manager Voyages Indigenous Tourism Australia, a subsidiary of the corporation, has reported losses of more than $100 million.
As well there has been a $62 million write down of the asset.
"We are doing a further valuation at the moment which could lead to a further write down," Mr Dillon said.
The corporation borrowed close to $200 million and is now facing an interest bill of $11 million a year.
