Many people who had moved away for work had since moved back to the area, she said. People had not wanted to move during the election lead-up, but now they were looking, there were not many rental properties available.
"I haven't seen [demand] like this at this time of year for a long time."
At the bottom end of the Northland market in Kaikohe, the average rent for a three-bedroom house increased slightly by $3 to $228. Nationally, the average rent for a three-bedroom house was up $15 year-on-year to $379 per week. A three-bedroom flat was up $11 to $381 on average, while three-bedroom apartments were down by $11 to an average price of $527. Apartments were also the most expensive mean property type for four bedrooms - up $84 to $669 per week, compared to a $52 increase to $490 for a house and an increase to $470 for a flat.
Tenants Protection Association manager Helen Gatonyi said she wasn't surprised by the rent increases, as it was common for the association to hear of tenants whose rents had increased by $20 or $30 or, in some cases, by $100 or more.
Landlords claimed they had kept rents down during tough economic conditions and were now just catching up, she said.
"In some cases landlords have kept prices down and now brought them up to a realistic level, taking into account rate and insurance costs, but altogether there is overwhelming evidence that there's plenty who are just taking the opportunity to make an extra quid," she said.
"The reality for many of those tenants is that they are simply getting further and further into debt and are not able to sustain it."
This had contributed to a big gap in disposable income for a lot of people, she said.
It was likely rents would continue to increase as supply and demand was still a huge issue that would not settle down any time soon, she said.
An August survey of landlords by Crockers Property Group found rates increases were the factor most likely to trigger a rent rise, but other costs such as insurance, property maintenance and interest rates were also relevant.