The government awarded renowned singer and artistic director Robyn Archer a four-year services agreement worth about $1.2 million to commission and oversee events at the year-long festival.

Liberal leader Jeremy Hanson, who has criticised some of Archer's decisions this year, has now questioned whether the deal gives Canberrans value for money.

He said the amount appeared to be "in excess of what the community expects".

However, Chief Minister Katy Gallagher praised Archer's unique skills and heavy workload, saying the creative director had attended "hundreds of events, either as a guest speaker or active participant".

"There is no comparative role in Australia, and as such there is no 'market rate'," Ms Gallagher said. "The government is wholly satisfied that Ms Archer provides excellent value for money."

Archer began her work preparing the celebrations in September 2009.

In the first year of her contract, in addition to her then $290,000 annual professional fee, she was entitled to a residential allowance of up to $24,000, $4000 to cover phone and internet costs, and $20,000 in travel expenses.

Her contract also compensates her for "reasonable out-of-pocket and entertainment expenses, including tickets to events, gallery admissions and meals with artists and relevant people".

The government has since increased the fee and allowances in line with inflation, suggesting her fee is now about $310,000 a year.

However, that amount includes GST and, as Archer is a contractor, she receives no superannuation, leave entitlements or sick benefits.

The appointment of Archer, an artist of international repute, was hailed as a coup for Canberra, though some of the centenary's higher-profile events have been controversial.

In March, the $3 million "One Big Day" celebration by the lake attracted a huge crowd of about 150,000 people.

But it upset some who attended, who complained there was too little food or water available in the hot weather, and said the artworks and performances were too highbrow.

Last month, former chief minister Jon Stanhope criticised a hot-air balloon commissioned for the centenary – the Skywhale, a flying creature with many large breasts – saying it invited Canberra-bashing.

"I hate to say it, because I admire Robyn Archer, and I was responsible for her engagement, but I have to say I think it was quite self-indulgent of Robyn and those around her that actually pursued this particular project," Mr Stanhope said when the balloon sculpture was unveiled.

Mr Hanson said the size of Archer's fee was "'inconsistent with the government's cuts across the board in [this month's] budget of $142 million, in reduced services and increased fees and charges".

"'The question is, is it value for money? Just like the Skywhale, the government's priorities don't necessarily reflect the priorities of the community," he said.

He also questioned whether the fee was excessive given Archer continued to perform duties elsewhere in Australia in addition to her work on the centenary.

However, Archer told Fairfax Media she could not compare her job or fee with other positions, as there were "no similar roles".

“Other festivals around Australia run for three weeks or less," she said.

She estimated she spent 85 per cent of her working time on centenary business, and gave some indication of what that involved.

"The time commitment is well over a standard working week. Fourteen-hour days are the norm, no nights off, no weekends off ..." she said.

"From January 7 till June 10 this year - 179 days - there have been only four days free of centenary commitments. I have made 120 public appearances, written 80,000 words for speeches and addresses, and attended another 87 events."

Ms Gallagher said the creative director had "more than delivered on the requirements of her contract while fulfilling her other commitments".

"She has often used these other roles to promote the centenary around Australia," the Chief Minister said.

Ms Gallagher earns $263,000 a year and will receive a superannuation pay-out when she leaves the Assembly.

Other MLAs' annual pay ranges from Deputy Chief Minister Andrew Barr's $225,000 to a backbencher's salary of $125,200. MLAs are also provided with a car.

The ACT Remuneration Tribunal agreed recently to freeze MLAs' pay in response to requests from politicians from all parties.

Ms Gallagher had cited the troubled ACT economy when she asked for the freeze.

"In a tight fiscal environment, I believe MLAs can cope without a pay increase in 2013-14," she wrote in April.