Her full-time job paid her between $16 and $19 per hour depending on her role but once she put more than $300 a week toward rent, bought food for the three of them and paid her sons' school and medical expenses, there was not much left to accommodate rising living costs, she said.
"When you're a single mum trying to pay $380 a week on rent, that's a big chunk of your pay packet.
"I'm desperate, I'll take anything," she said, forced to apply for rentals she knew were too expensive for her budget.
Ms McAllister said she was issued her 42-day notice after only three months living at the property.
"I found it in the letterbox on Christmas Day," she said.
A friend took Ms McAllister and her two sons in when their 42 days ran out without being able to secure a new rental.
They shared a bedroom between the three of them for a week before moving to stay with another friend.
"This lady has been good enough to put a roof over my head ... but I can't stay forever."
Last week she turned to Te Tuinga Whanau Support Service for help and social worker Jenna Young said her case was not unusual.
"I would have about 15 cases a week, if not more," she said.
"We need the Government to see how bad it is because we're seeing it every day."
The "housing crisis" was the worst she had seen in her five years at Te Tuinga and it had been becoming increasingly worse since about August 2014, she believed.
Fewer homes and more competition meant increasing rent prices and tougher landlords, she said, making it very hard for people like Ms McAllister to have a chance with a bad credit rating.
She understood the agencies in charge of housing were doing the best they could given the circumstances and stressed it was a Government issue.
A Ministry of Social Development spokesperson said it was working with Ms McAllister to finalise her social housing application.
Once her application was approved she would be added to the social housing register and Housing New Zealand and community housing providers would look to match applicants to an available and suitable property.
Housing New Zealand area manager Teresa Pou said they had a total of 1384 properties in Tauranga and the Western Bay of Plenty.
"At any given point in time, some will be vacant while they're between tenancies. In the past six months, we housed 247 families in Tauranga, Rotorua, Whakatane and Gisborne areas," she said.
Nationwide, 3658 cases were on the housing register and the biggest group was the 1441 cases of one parent with a child or children, similar to Ms McAllister.