Li is already serving a life sentence with a minimum non-parole period of 16 years for his part in the murder.
Police found Kiko's body riddled with 22 stab wounds in the boot of her car which had been dumped in Hamilton.
Text messages between Yu and his friend Yongxin Li were read to the court during Yu's trial.
They revealed that the pair planned to pick out a victim from a rich family then drive to Piha, on Auckland's west coast, for the stabbing.
One of the text messages from Yu to Yongxin Li read: "Kiko has probably quite a lot of money in the card. Family is also very rich. May consider it. Furthermore. I know her pin''.
But Yu was wrong. Soon after the killing, Yu was captured on CCTV at a bank trying to use Kiko's ATM card. The card was eventually swallowed by the machine.
The court heard he and Yu bought a knife from a supermarket before the murder.
On the night of the killing, Yu was giving Kiko a driving lesson. Yu was behind the wheel, Kiko was in the passenger seat and Li was in the back.
At his trial, Yu told the court he didn't know Li intended to hurt Kiko and said he had been driving "aimlessly'' towards Piha.
He said he was chatting about his relationship problems before Li reached over from the back seat and tried to strangle Kiko.
Li then produced a knife and stabbed her, he said.
However today, Crown prosecutor Aaron Perkins described Yu's actions as deliberate, and said he and Li were "equally involved in the offending''.
Yu's lawyer, Mark Edgar, separated the two offenders, saying "it was Mr li's persistence that carried the offence''.
Yu also felt regret and remorse for his actions, he said.
At Yu's sentencing Justice Toogood spoke of the "deep grief and psychological harm'' suffered by Kiko and Yu's families since the murder.
In victim impact statements read to the court today, her father Chang Kui Li said the "loss of my daughter has plummeted my life to the bottom''.
"I shut myself off by staying at home. Often I stare at my daughter's picture in a trance.''
Since Kiko was "taken away by a cruel act'' and his business had also suffered as he had been unable to concentrate on work, he said.
Kiko's stepmother said she felt "helpless and desperate'' since the murder.
"How can I stop my heart from being torn to pieces in deep grief,'' she wrote.
In a letter to the court, Yu's parents described their son as kind, polite and loving, and a student who had respected his teachers and got on well with his classmates.
