Vernon Ruwhiu promised to manage 65-year-old Takangaroa Moanaroa's retirement savings for her benefit.
Instead, he took her savings and used them for his family's benefit after establishing a family trust - but not on terms agreed with Moanaroa.
The High Court has ordered Ruwhiu and two others to pay Moanaroa, who lives in Whangārei, more than $500,000 in total for breaches of fiduciary duty after Moanaroa took legal action to recoup her loss.
She met Ruwhiu at a seminar about mortgagee sales in 2003, at a time a property she part-owned in Whenuapai was to be sold under a mortgagee sale.
Moanaroa wanted to invest savings she had of $61,000 into buying a house in Whangārei for her retirement in 2006.
Ruwhiu spoke to her about how to manage her wealth as part of a scheme to help families struggling to pay their mortgages and suggested setting up a trust.
He established the Kaiawhina Family Trust in November 2003 with he and Denise Ruwhiu named as trustees who enjoyed broad powers to use the trust money.
She received $238,113 from the sale of the Whenuapai house and Vernon put $223,373 from the proceeds in a bank account under the trust's name.
How the proceeds would be dealt with was not made clear to her at the time.
She assumed they were lent out on short-term loans which would mature in time for her to buy a home in Whangārei.
Vernon and Denise Ruwhiu bought a house in Whangārei as trustees and applied trust money of $145,200 to pay instalments.
Monaroa thought the property was purchased for her.
When the trust fell into arrears, Vernon Ruwhiu's sister Bonnie Ruwhiu obtained an interest-only mortgage over the property for $175,000 and paid the settlement sum in October 2017.
He then arranged for Bonnie to become the sole owner of the house after which she also became a trustee .
Moanaroa stayed in the house as a tenant but was evicted in 2015 following a mortgagee sale after Bonnie defaulted on the interest repayments in 2014.
Justice Christian Whata said the breach of fiduciary duty involving the deceptive taking of an elderly woman's savings is outrageous.
With independent advice, the judge said Moanaroa would never have consented to the transfer of her money to the trust over which she had no control and through which the Ruwhius could directly benefit.