On July 5 2011 Douglas went to Stephen Hill Motors in Napier and purchased a 2006 Clubsport R8 with the $51,000 bank cheque.
He originally registered the car in his own name but it was changed just a few days later.
Later the same day he withdrew another $30,000 from his account and transferred $14,948.32 to the Oxford Finance Corporation.
The next day he met an associate, Barry Bell, at a car yard in Hastings where he purchased a 2002 Holden Commodore SS ute for $17,000.
The car was registered in Bell's name and was later traded in for a 2002 Holden Clubsport which was also registered to Bell.
A couple of days later Douglas went and purchased a 2002 Holden Commodore VX and paid the $15,500 purchase price in cash.
The vehicle was registered in his daughter's name and was onsold two months later with the proceeds going towards the purchase of a 2007 Holden ute.
The BNZ discovered its mistake in early September 2011 when Douglas' mortgage payments went into arrears.
Douglas told the bank he had won some money on a lottery and had been expecting a Winz payment around the time the large amount from the bank was credited into his account.
He told the bank it was normal for him to make $50,000 withdrawals. Three vehicles, a 2004 Holden ute valued at $34,990, a 2006 Holden Clubsport valued at $51,000 and a 2004 Holden Maloo valued at $35,990 were recovered by police.
The ute and the Maloo were the end result of Douglas trading the vehicles he bought for cash back.
An order was sought by the BNZ to repatriate the Clubsport purchased with the bank cheque.
The bank is also taking action through the civil court to recover money owed to them.
Douglas was also found guilty at trial of assault with a weapon and will be sentenced on all matters on December 12.
In a statement, a BNZ spokeswoman said Douglas used funds that were incorrectly allocated to his account due to a "keying error".
"When BNZ contacted Mr Douglas he said he won some money from a lottery.
"Debt recovery was undertaken through the bank's usual processes and the matter was forwarded to police for criminal investigation."
The spokeswoman said nobody was available to be interviewed on the subject.