The Tenancy Tribunal was called upon to intervene in more than 38,000 disputes last year - and most of the complaints were against tenants.
Just a tenth of them were brought by tenants against landlords, and the remaining 34,000 were landlords pursuing tenants.
These figures come from the Ministry of Business Innovation and Employment (MBIE), within which the Tenancy Tribunal sits.
Now is a busy time for renters looking for new flats for the coming year.
In parts of the country - particularly in Auckland - tenants report huge competition for flats, with queues forming to view certain properties.
Meanwhile, a select committee is considering a law change requiring insulation and smoke alarms in all rental properties.
So what does the Tenancy Tribunal offer tenants and landlords when things go wrong?
Kevin Reilly is from the Manawatu Tenants' Union, which was established 33 years ago and assists more than 1000 tenants a year.
He said the Tenancy Tribunal was an improvement on the way things were.
"It's better than the law of the jungle, which is what existed before. It's a lot more equal, not completely equal, but a lot more equal."
However, disputes could escalate.
"Sometimes it's warfare between landlords and tenants when it gets to the tribunal."
Another problem was despite there being a legal framework which set out rights and obligations, tenants were poorly educated.
"A lot of people have got no idea of their rights and obligations."
He said the most common complaints were to do with repairs and the condition of premises.
His organisation was advocating for a Warrant of Fitness system for rental properties, such as the one which has operated in Palmerston North since 1995, and for landlords to be licensed.
He said the tenant-landlord relationship was far from equal.
"The whole rental market is about power and control. Tenants do have some rights under the Residential Tenancy Act and some assistance with the Tenancy Tribunal, but at the end of the day the guy that owns the house controls everything.
"[That's] because in New Zealand there is no security of tenure."
A tenant could have rented a property for 40 years, yet still got only 90 days' notice to leave.
But Paul Davies, from tenancy services at MBIE, did not believe there was an imbalance of power between landlords and tenants.
He said the reason most disputes originated from landlords was because most concerned unpaid rent, and he believed there were good mechanisms to resolve problems before a matter reached the tribunal.
First the two parties must try to come to a mediated or negotiated agreement; there were 21,588 such mediations last year, of which 80 percent were resolved.
Listen to Kevin Reilly of the Manawatu Tenants' Union and Paul Davies of Mbie's Tenancy Services Team talk to Kathryn Ryan.