"Most come from overseas and they're moving to an empty house," she said.
It was common for international students to live in such a way because they arrived in New Zealand having to pay international student fees and couldn't afford living costs. She said some also used foodbanks because they were struggling.
Two Waiariki International students said they both lived in separate one-bedroom flats with three others. They shared bedrooms and the living area with other students, paying rent of about $40 each.
While it was hard without their own space, the students said they couldn't afford to live any other way.
One of those students, a 20-year-old IT student, said as part of her visa she could work 20 hours a week but found it hard to secure a part-time job, despite signing up with Jobsearch.
A 19-year-old hospitality student said she also struggled to find work, which was why she was forced to live with three others in a one-bedroom flat.
They said the maximum number of tenants allowed in their flat was two.
Waiariki director of special services Paramdip Singh said international students could pay about $18,000 in fees and although they saved a bit of money before moving here, most assumed they could pay for their everyday living costs through working to support themselves.
However, jobs were scarce due to the recession and the Psa disease affecting kiwifruit orchards in Te Puke.
He said hundreds of their students relied on the kiwifruit industry for part-time work.
Although many students were from middle to upper-middle class families, they didn't want to ask parents for money.
Richard Evans, of Rotorua Rentals, said it had a few international students who rented properties but Rotorua didn't have a big student market.
"We're not aware of overcrowding ... it doesn't mean to say it doesn't exist."