A man whose home was repossessed by the Commonwealth Bank (CBA) later discovered his signature had been forged and his salary falsely inflated on loan documents, the Victorian Supreme Court has heard.

Key points: The Parkers had $4m worth of properties repossessed in 2007

The Parkers had $4m worth of properties repossessed in 2007 They were unabele to meet payments on a CBA loan

They were unabele to meet payments on a CBA loan The couple say the loan was based on documents forged by the CBA

Jim and Debbie Barker said they were now financially ruined and asked the court to set aside a default judgement which ordered them to pay the CBA's costs.

Setting aside the costs would to allow them to seek compensation from the CBA.

They said the bank seized their home and other properties totalling up to $4 million in 2007 after they were unable to pay an investment loan for a development on Phillip Island.

Ms Barker said it took her more than four years of persistent requests to obtain the loan documents, at which time she discovered money had been drawn down without their consent, the loan amount increased from $1 million to $1.5 million, her husband's signature had been forged and his salary documented at $343,000 a year despite him earning no more than $80,000 per annum.

"I saw seven or eight different bank managers and not one of them said to me, 'Deb, your husband earns $343,000 a year, that's how you've got such a big loan' - I would have fainted," Mrs Barker said.

"Emotionally we're also ruined ... in the last 10 years my mum's died but all we've done is live this and tried to get some help.

"We've lost everything: our well-being, we haven't had time with our grandchildren, we don't live, we just exist."

CBA breached code of practice: lawyer

Their lawyer, Joseph Tsalanidis, told the court that the CBA had breached the code of banking practice because it "did not act fairly, properly... and ethically".

"The court ought to now set aside the judgement [against Mr Barker] to enable all matters to be investigated ... and not deny a man who says 'I want my day in court, for the facts to be revealed and exposed'," he said.

He said one letter allegedly signed by Mr Barker requested a draw down of $882,000 but it was "a forgery: no such request was made to draw down the funds."

Mr Tsalanidis also pointed to the close relationship between a CBA bank manager who has since died and a mortgage broker who is now facing fraud charges.

He said the facts of the case warranted an investigation of that relationship and "the movement of a significant amount of money out of customers' accounts".

But he conceded these matters could have been addressed in a November 2014 court hearing that Mr Barker failed to attend and which led to the default judgement against him.

"[Mr Barker] says [he] was on medication, was under stress and anxiety and could not afford a barrister to attend," Mr Tsalanidis said.

But CBA lawyer Maryanne Loughnan QC said she would have much more to say about the background of the case and described Mr Barker's argument as "tenuous".

Giulia Mandarino (left) hugs Debbie Barker outside the court. ( ABC News )

"He has entered into a loan agreement with someone so they can get this money," she said.

"Mr Barker has waited six or seven years for other people to have a go at [the mortgage broker facing charges] and then he could jump on board."

Associate Justice Robyn Lansdowne agreed with CBA's objection to including media reports on the CommInsure and CBA financial planning scandals in the case, ruling they were irrelevant.

Outside court, Giulia Mandarino, who has lent support to the Barkers after losing her own home in similar circumstances, said she had collected 30,000 signatures on a Change.org petition against corporate bank fraud.

"We've been overwhelmed by the messages from around Australia and overseas and people are calling for a royal commission," she said.

"It has really changed our lives in the past week - we asked people to stand behind us and it has not gone unnoticed."

The Barker's case was adjourned until April.