"We always wanted to have a solely New Zealand-made store. We had seen the potential and really wanted to split the businesses," says Pritchard.
Some people seeing second-hand furniture outside the existing store may have been put off venturing inside to see the contemporary gifts, says Knott.
It's been a brave move for a business that admits to having had flat growth over the past year, for the first time in its nine years of operation.
The Rugby World Cup was terrible.
"The locals stayed away and we had no tourists - that was a tough end of last year," says Pritchard.
But having just opened the new store at 504 New North Rd, the couple are already getting a good response to the separate businesses.
"We made a multiple sale yesterday that I don't think we would have made before. I don't think if it had been alongside the retro stuff it would have happened," says Knott.
Many customers for that part of Mixt are buyers of gifts - necklaces, wooden objects, prints, pottery, textiles - for family and friends overseas.
The company is careful about pricing. In the past year it has reduced the number of expensive items in its range and expanded the lower-price range. That means having to sell larger volumes but that's the way the gift market is going, says Knott.
The couple, who live in Kingsland with their 5-year-old, are experienced retailers. Knott has been in the industry for 25 years, starting with antiques and collectibles, while Pritchard, who has an art background, had a shop in Devonport.
Mixt, their first business as a couple, was started in 2003 after they met at Webb's auction house.
Mixt does without a website, but has a Facebook page with about 3000 followers. The couple have launched a Facebook online shopping app.
They run the business, which has turnover of under $1 million, together, with one employee.
The new store is opening in time for Christmas, which typically accounts for a third of profit, says Knott. "Now that we have split this, it's not inconceivable that we would consider having another shop.
"If we ever opened anywhere else it would be Devonport."
Top tip
Make sure you have a well-defined point of difference and that you think carefully about your stock and your market. Are you selling something for which there is demand and is it priced appropriately? Make sure you are prepared for a lot of hard work.
Best business achievement
Still being open after nearly nine years. Being known for our constantly evolving style, supporting local artists andobject-makers and being lots of people's favourite shop.