"We have lots of products - big, big deliveries arriving and we need a proper system where we can unpack it all."
She was looking for a new place in the city and Ponsonby, but there was not much on the market.
"We're really, really loath to move because we love it so much.
"I really do know what I want in my head and if it doesn't fit my brief then I don't go and look at it. I really think I need to wait and see what this one sells for.
"Having looked around, I absolutely know there's nothing like our place on the market at the moment. It's inner-city and with car parking, which is unheard-of, and it has an incredible history."
World, which was started in 1989 by the designer and her ex-husband Francis Hooper, now has clothing stores in Britomart, Ponsonby, Newmarket and Wellington and beauty stores in central Auckland (Vulcan Lane), Ponsonby, Wellington and Mt Eden.
The brand sells in Australia, Europe, the United States and Asia and has shown at London, Paris, Hong Kong and Singapore fashion weeks.
Ms L'Estrange-Corbett said she has had a handful of architects and art directors look at the property, which is marketed by Bayleys.
Records show World bought the building off the Art Barn Picture Framers in 2005 for $875,000.
The company was first based on the fourth floor of an office building on High St, which was inconvenient for deliveries, Ms L'Estrange-Corbet said.
It's current 255sq m building, which sits on a 405sq m section, has two billboards on site which are illuminated by spotlights at night and generate a combined revenue of $35,439 a year. It has enough parking for six cars.
It was once the biggest Wesleyan school in England's colonial empire - with more than 100 pupils attending from neighbouring suburbs along Karangahape Rd, Newton Gully, and Ponsonby. It is now recorded as the oldest surviving school building in Central Auckland.
"We've got pictures of it when it was just a little church sitting on the top of a grassy knoll, with nothing but sheep," Ms L'Estrange-Corbet said.
Bayleys real estate agent Clint Barber said the church remained "virtually true to its original facade and interior layout as the former Wesleyan chapel - with large intricate arch framed windows, polished tongue and groove timber floors, red brick walls, and an exposed cathedral-style roof and beams".