Landlords Link managing director Tracey Onishenko said the better the property, the better the tenant.
"There's some absolute nightmares in Wanganui, and there have been times that property managers have taken anything on. But when you've got places that are unliveable, you're attracting the people that've been kicked out from four or five other places and the owners will just put them in because they need the money."
However, the company had raised its standards - with good results.
"The last three years we wouldn't take anything we wouldn't live in so you're getting better tenants and you're not really having any problems."
However, good tenants could become bad tenants overnight and landlords should look out for changes in attitude.
"If they're super neat and pay their rent and then all of a sudden the house is messy and they've got extra people ... usually it's a sign they've hooked up with someone and they're on drugs," she said.
"We keep a really close eye on that because we've had tenants who were perfect for two years and then all of a sudden have got in with the wrong crew and turn bad."
Last year, Wanganui councillor Jack Bullock was threatened with bankruptcy shortly before the local body election over unpaid rent. In May 2011, the Tenancy Tribunal ordered him and a former partner to pay $6500 in unpaid rent and damage to a house they had lived in.
The Tenancy Tribunal is a special court which deals with problems landlords and tenants can't settle.
Nationally, 45,045 complaints were filed to the tribunal last year - a rise from 41,910 in 2012.
Property Investors Federation president Andrew King said tenants often used "sad tales" to waylay landlords' attempts to chase up lost rent.
"Things like 'The kid's sick and has to go to hospital' or 'Someone's died' ... or 'the car's broken down, the washing machine's broken down'."
Sometimes tenants were telling the truth, but there was "no way" to know.
"And once they stop paying rent, they get very used to it and it'll happen again and again."
Tribunal applications take about seven weeks to process, and could cost landlords about $3000 in lost rent pending a hearing.