Three expensive paintings by a major Australian artist have had their authenticity cast into doubt, just a few years after each sold for hundreds of thousands of dollars.

Key points: The three paintings by Howard Arkley had a combined valuation of almost $750,000

The three paintings by Howard Arkley had a combined valuation of almost $750,000 One buyer says the painting he bought for $200,000 is worth $20

One buyer says the painting he bought for $200,000 is worth $20 The three pictures can all be traced to the same group in Melbourne's art market

All had been attributed to Howard Arkley, best-known for his dayglo paintings of Australian suburban houses, who died of a heroin overdose in 1999.

Each of the three suspect works can be traced from their current owners back to a single group of high-profile identities in Melbourne's art market, a Background Briefing investigation has revealed.

"There's been a concerted effort by a consortium of people," Andrew Crawford, a veteran art dealer and gallery owner, told the ABC.

"A conservator with the know-how, technical expertise; an artist — the mastermind; and the disseminator into the public marketplace."

Two paintings with the same origin

Completed during a flurry of creativity, Arkley's Family Home painting was first exhibited in 1988 and sold to controversial Melbourne art dealer Peter Gant for $8,500.

Nearly 20 years later, Family Home broke all the artist's previous records when it attracted a bid of $407,000 at an auction by Joel Fine Art.

There was just one problem: it was not the same painting as the 1988 original, as Australia's leading expert on Arkley, John Gregory, has acknowledged.

Although quite similar, the second work bears several key differences.

The painting on the left was originally bought by Peter Gant in 1988, the one on the right was sold under the same name for $407,000. ( Supplied )

The receipt from the original 1988 sale was used by an unknown seller to establish the provenance of the second painting, according to Joel Fine Art's former CEO John Albrecht.

The fate of the original $8,500 painting and the origin of the second work remains unclear.

The ABC understands the Estate of Howard Arkley will not grant copyright to the second work — the one which sold for $407,000 — as there is no evidence it was produced before Arkley died in 1999.

Why Arkley paintings are in dispute

The dealer at the centre of this controversy, Peter Gant, once had a thriving trade in the Melbourne art world.

His dealership fell into decline after he was embroiled in a criminal court case over three paintings, which were sold or attempted to be sold for $4.5 million, and he said were by celebrity artist Brett Whiteley.

Whiteley's estate and many art experts disagreed, and the case ended up in the Supreme Court of Victoria, where a jury found Mr Gant and his business partner guilty of two counts of obtaining financial advantage by deception and one count of attempting to do so.

Howard Arkley in front of one of the houses he painted. ( Supplied: Martin Kantor )

Both were later acquitted on appeal, when a judge decided there was insufficient evidence to prove criminal intent.

Following the court cases, many art collectors who own paintings that have passed through Mr Gant's ownership have sought advice on whether their prized possessions are the real deal.

Gallery owner Andrew Crawford said there was a significant number of forgeries by major Australian artists in circulation and art buyers had been getting fooled.

"With Whiteley we know that there are between four and 10 significant oils that are reputably by him, but most probably aren't," Mr Crawford said, "there are certainly dozens of works by Arkley that are problematic".

Arkley's eccentricities provide cover for people trying to sell fake paintings as true Arkleys, according to Mr Crawford.

"It was the poor record keeping and his lifestyle which they managed to take advantage of," he said.

Arkley's close friends said he was often cash-poor, and he would sell rushed works at bargain prices to get money for heroin.

"He would be known to sell a $1,000 drawing for $250," said his friend and author Dr Ashley Crawford — no relation to Andrew.

Dr Crawford added even though Arkley's work was chaotic, he painted a substantial amount, further adding to the difficulty of tracking what is genuine and what is not.

"It could be one o'clock in the morning. He could have had all sorts of substances, certainly a great deal of champagne — his favourite drink, usually warm — and he just couldn't stop working."

Painting sold in London in doubt

The ABC has learnt, another painting attributed to Arkley, called Pink House, also lead to a dispute over authenticity.

Mr Anderson said he was eventually refunded by the auction house that sold the painting. ( ABC News: Scott Mitchell )

Featuring a similar dayglo suburban house to Family Home, Pink House last sold for $200,000 at the prestigious Christies auction house in London.

The successful bidder was Sydney art collector Rick Anderson.

"Having the backing of a major English auction house Christie's I thought well there's nothing really going to be wrong with this picture," Mr Anderson said.

He soon learned the painting was sourced from John Playfoot, who had helped Peter Gant sell one of the dubious Whiteley paintings that featured in the Supreme Court case.

Mr Anderson sought to prove its bona fides with the assistance of Australia's foremost expert on Arkley, John Gregory.

"He wrote a report damning it, saying these are the inconsistencies in the picture," Mr Anderson said.

Mr Anderson told Background Briefing he sought advice from art forensic specialists, who confirmed the bad news.

"It's a $200,000 picture hanging on my wall that was worth 20 bucks," he said.

According to Mr Anderson, he was discreetly refunded the full $200,000 years later.

A forensic examination of the painting came back with bad news for Mr Anderson. ( ABC News: Scott Mitchell )

But a record of the original $200,000 sale remains on the Christies website with no indication it later refunded Mr Anderson in full.

Christies declined to comment about the incident, citing confidentiality.

Forensic inquiry into third painting

Background Briefing also obtained a confidential report raising serious questions about a third work, Greek Style.

It was last sold by John Playfoot for $130,000 to a Sydney collector in 2008.

An expert from Melbourne's Centre for Cultural Materials Conservation examining a painting. ( ABC News: Michael Barnett )

The confidential report, written in 2015 by leading forensic analysts at Melbourne's Centre for Cultural Materials Conservation, identifies a large number of irregularities in how the painting was made.

"'Overall, the method of the canvas attachment, the uncharacteristic style of the underdrawings, the application of paint and ground, the surface finish, the lack of highlight and shadow, and the diversion of the composition layout from the preliminary drawing/template, means that with the knowledge we have at this time relating to Arkley's materials and techniques, this painting cannot be placed into the oeuvre of Howard Arkley," they concluded.

Two years after the report was finalised, a Sydney art dealer attempted to consign the tarnished work to auction house Deutscher and Hackett.

However, Arkley's estate refused to grant copyright for the painting to the company's executive director, Chris Deutscher — effectively shattering its value.

Peter Gant, John Playfoot, and Kalli Rolfe from Arkley's estate all declined interview requests.

While these cases show there is now a heightened risk in acquiring a piece of Arkley's celebrated oeuvre, his work has been more in demand than ever.

Last month, his 1992 painting, Deluxe Style, attracted a $1.5 winning bid at a Menzies Art auction in Melbourne — setting a new record for the artist.