"It is not uncommon for us to have 25 groups register for a viewing and 20 show up."
Rental prices were still rising, Mr Hocquard said, and the Trade Me figures did not take into account the quality of properties.
"Rents have probably gone up 5 per cent at least."
The Wanganui Chronicle reported in April that up to 40 people were competing to rent a property.
Mr Hocquard said Ray White had perhaps one or two more properties available than at that time.
Property Brokers' Philip Kubiak said few properties were currently available to rent, which was reflected in the prices.
"The private rental market is tight and good rents are being achieved."
Property Brokers had just seven properties available to rent, Mr Kubiak said.
"That can fluctuate between 5 and 15...two or three years ago, we would have had 30 or 40."
In the second week of April, Property Brokers had just four properties available for rent.
Rental prices last month remained 8 per cent higher than in June last year, when the median weekly rent in Whanganui was $240.
This was a larger annual increase than the average in the wider Manawatu-Whanganui region of just over 5 per cent.
Regional rental prices rose by $5 a week from May to June - from $295 to $300 a week.
At a national level, rents have remained the same since January this year.
Rent rises have slowed in most parts of the country, Trade Me head of property Nigel Jeffries said.
"I'm sure these numbers will be a relief for the many tenants who have felt big rises in recent years.
"They'll be pleased to see the brakes have stayed on but not everyone will be happy as a number of regions are still seeing strong rent inflation."
The average rent across the country from June to January was $450 a week.
The highest increases in rental prices from June 2016 to June this year were in Northland and Wellington, where prices increased by 15 per cent and 12.5 per cent.
Canterbury was the only region where prices fell over the past year - by just over 1 per cent.
There was no change in Taranaki, Marlborough, or the West Coast.
The highest median weekly rent was in Auckland, where properties averaged $530 a week, just over twice the median rent in Whanganui.