The purchase of two cars, including a VW Polo, a DVD player, other household assets, and day-to-day living meant she had spent $48,000 more than she had earned in the 13 months before Mr Nisbet's death, the court was told.
"Helen Milner was not living within her means or available income," Ms James told the eighth day of the high court murder trial.
To make ends meet, she was borrowing against her mortgage and putting herself further into debt, she said.
It also emerged that $28,000 of unexplained income was, in fact, money stolen from Christchurch grounds maintenance firm, GSL, where she worked as an office administrator. She later admitted a theft charge relating to her time at GSL, where colleagues had nicknamed her the 'Black Widow' after she had talked about poisoning Mr Nisbet.
Milner denies murdering 47-year-old Mr Nisbet by giving him a fatal overdose of the antihistamine and sedative Phenergan, and possibly finishing him off with a pillow over his face.
Police originally ruled his death was a suicide.
The Crown claims Milner was unhappy in her marriage and motivated to murder by the prospect of cashing in the $250,000 life insurance policy.
She plotted the best ways to kill her husband; buying drugs under false names, asking friends for views on poisoning methods, and even offering to pay $20,000 for a hitman to kill Mr Nisbet, it is alleged.
Milner also denies attempting to kill him twice on April 15, 2009.
Ms James was tasked to look into Milner her and late husband's finances in June 2011 by detectives who launched a homicide inquiry after a coroner raised doubts over the death.
The forensic accountant told the jury that while the property they lived at was in Milner's name only, it would have become 'relationship property' if the couple had divorced and meant that Mr Nisbet would have been entitled to half.
Ms James found that Mr Nisbet, a delivery driver, was living within his own means, and was still making monthly payments on a debt to Inland Revenue.
Milner's spending however was putting her further into debt.
The trial, before Justice David Gendall, continues tomorrow when the Crown case is expected to conclude.
Nisbet's log book not filled in
Delivery driver Phil Nisbet had not been filling out his log book properly in the weeks leading up to his death and had cleared his personal mementoes from his truck just days before he died, the court heard today.
Helen Milner told his family after his death that he had just been diagnosed with the sleeping disorder, narcolepsy which meant he would have to give up his beloved job.
Former workmate Ray Carey said Mr Nisbet's logbook had not been filled out since April 28 - six days before his death.
"It was out of character for him."
Personal items, including a chain hanging from the rearview mirror, had also been removed from the vehicle, Mr Carey said.
