Renters were looking more broadly to find a place to live, she said.
"I've talked to a lot of people who say they just can't find something so they're looking for something out of their price range," she said.
"They need something and they're willing to take anything. They're looking above and below."
There were several houses priced at $2500 a week, commonly leased to corporate executives moving from overseas. A 12-month stay was typical - adding up to $130,000 - and it was often the companies paying for the accommodation during a relocation, Ms Sheppard said.
A "resort-like" five-bedroom house at 427 Riddell Rd, Glendowie, is advertised as having its own micro-climate, with its sweeping grounds home to a tennis court. For $2500 a week, grounds and pool maintenance are included.
Per room, the most expensive rental may be a three-bedroom penthouse apartment in the Lighter Quay North complex in Halsey St at the Viaduct, going for the same price. It promises the "ultimate inner-city living" - at least for anyone who can afford it.
Photos show a wide balcony looking out to the marina, and stylish living areas accented with black walls and furniture.
A five-bedroom rental villa in Grey Lynn goes one notch higher, priced at $2700 a week.
"We don't have houses like this come up very often," Ms Sheppard said. "We've got a couple that are high end - but the one in Grey Lynn, it's a very special kind of house. You wouldn't find that for rent or sale much at all."
The property, at 334 Richmond Rd, covers 1876sq m. It has a large heated pool with multiple depths and an outdoor kitchen with a pizza oven.
Wellington and Christchurch both have $2500 a week houses on the market, while holiday homes around the country are priced even higher.
In Queenstown, "executive accommodation" overlooking Lake Hayes is available for $3000 a week - or $18,450 upfront including letting fees, rent in advance and a bond.
