The administrators of collapsed auction house Mossgreen have been ordered to return thousands of precious antiques and heirlooms, after the Federal Court ruled they did not have the right to slug owners a fee to hand the items back.

Justice Nye Perram found the administrator, BDO Australia, was "intermeddling" when it tried to charge people a $353.20 collection fee per item.

BDO Australia has been ordered to report back to the court within the next seven days with its response.

Neil Robertson, 62, decided to sell hundreds of antiques through Mossgreen after he was diagnosed with advanced bowel cancer and given a year to live.

He was charged more than $104,000 to get his items back, which are worth about $70,000.

Mr Robertson is currently unwell in hospital. His niece, Catherine Cohen, said the family was "incredibly happy" with the court's decision.

"For him, he gets those back and that's the most important thing," Mrs Cohen said.

"Hopefully it changes the industry and no one else has to experience what we've just experienced."

Toy collector Antony Davies, from Braidwood in NSW, launched legal action with more than 1,000 other people after being told that he would have to pay $27,549.60 to get his items back.

They were worth about $17,000.

The most important thing is that Mr Robertson gets his items back, said Ms Cohen. ( ABC News: Scott Jewell )

Mr Davies said the battle was about more than just his items.

"It was the principle which was really an outrageous case of confiscation," he said.

"I find their behaviour just unconscionable."

Mr Davies said he would be furious if BDO Australia appealed against the decision.

"I would imagine they will simply move on, and in a week or so I would expect people might be able to go and collect their property," he said.

Administrators 'not justified' in asking for fees

Mossgreen, known for selling artwork and rare collectables went into voluntary administration in December.

BDO Australia is holding more than 10,000 items on consignment at four sites in Victoria and one in NSW.

A painting being held by Mossgreen that belongs to Neil Robertson. ( Supplied: Debora Mullins )

Collectors were initially told in January that their goods would be returned, but weeks later received a letter which said they would need to pay a $353.20 levy to cover the costs of "identifying, preserving and maintaining" their items.

"To discharge their statutory function of realising company property, [BDO Australia] had to ascertain how much of what they held actually belonged to the company," Justice Perram said.

"That is not the case here where it has never been in doubt that the consignors own all of the property and, correspondingly, that Mossgreen owns none of it.

"They are not justified in requiring the consignors to pay a levy for the return of their goods."

BDO Australia has been contacted for comment.