In it he said Murden was directly responsible for the management, care, and sale of about $1million worth of cars to second-hand vehicle dealers in Northland and Auckland.
His monthly sales and transactions would be between $450,000 and $600,000.
Mr Illerbrun said the time and training the company had invested in Murden was significant.
"The time in which he has taken to organise his deceitful private sales of stolen assets is also significant.
"A personal betrayal of a senior manager to his colleagues, employers and other staff members and its effect on their well-being and ability to earn a living cannot be measured by money alone," he said in the victim impact statement.
The police summary of facts said Murden took a Nissan Safari home without the company's consent and it was found to be damaged when the car was returned to IC Motor Group.
On another occasion, he took a Nissan Navara home for two days without permission.
The cars he fraudulently sold through word of mouth to people in the Whangarei Heads area included a VW Golf for $5000, a Ford Escape for $1000, and a Jaguar for $5000.
Murden's dishonesty came to light after a person he sold one of the vehicles to inquired with IC Motor Group about documentation for the sale.
In explanation, Murden said he took too much on, was under a lot of pressure, was not making much money at work, and admitted making bad calls.
He paid $11,000 back to IC Motor Group and attended a restorative justice conference with Mr Illerbrun.
Judge Greg Davis sentenced him to four months' home detention and ordered that he pay $2983 in reparation to his former employer.
Outside court Mr Illerbrun said he had expected the outcome considering the fact Murden was a first-time offender who pleaded guilty at an early opportunity.
"The true cost of his dishonesty may never be known but it's significantly more than what has been suggested in the pre-sentence report," he said.