After eight months his past caught up with him - but in a positive way.
He bumped into former Warrior Kuripitone "Tony" Tatupu, whom Mr Mihaere had got to know when he played high-level rugby league himself.
Mr Tatupu, by then a police officer and member of the Lifewise outreach team, referred Mr Mihaere to support services at the Auckland City Mission and Lifewise, and with their help and his mate's continued support, he began to turn his life around.
Through Lifewise, he enrolled in a mental health and addiction course. He graduated top in his class.
Mr Mihaere, now 50 and a support worker for Lifewise, has lived in a rented home for six years.
His "lived experience" on the streets helped him to empathise with Aucklanders sleeping rough, he said.
Lifewise chief executive Moira Lawler said keeping a connection to the community was essential in helping rough sleepers back into accommodation.
Although Auckland's housing crisis had led to homelessness becoming an increasing problem, many rough sleepers still felt as though they were "invisible", she said.
"People kind of start to exist in a parallel universe, where they give up hope that they will ever engage again with a so-called ordinary society."
Mr Mihaere agreed. During his time on the streets, he was disconnected from both the homeless community and wider society, he said.
Life was a constant battle, particularly during the colder months.
He would go to foodcourts to "go tabletop diving", waiting until someone had finished and then "jumping in to eat the leftovers", he said.
Having a hot shower was a "very rare" luxury, but because he took pride in his appearance he braved the cold public facilities at the Domain.
Ms Lawler said more than 100 business and community leaders would experience a night on the streets during Lifewise's annual Big Sleepout tomorrow.
At the event, past and present rough sleepers would share their stories with participants, including teams from organisations such as Vodafone and Westpac.
Going without
• The Big Sleepout, now in its seventh year, is Lifewise's annual fundraising event.
• Tomorrow, July 7, at 5pm more than 100 business leaders will sleep rough to raise money and awareness of the growing problem of homelessness in Auckland.
• It will take place at the AUT University city campus quad, 55 Wellesley St East, Auckland CBD.
• The organisation aims to raise $400,000 for its Housing First initiative through the sleepout.
• Members of the public can donate to particular rough sleepers or to the overall cause online.
Donate or find out more at bigsleepout.org.nz