Their mark-up is enough to make a profit but still undercuts big-store competition.
Toby said the process had taught him to take risks and his parents had coached him in the basics of business.
"For our second order we decided to pay more for the fastest shipping because we didn't want to have any left over if the fad ended," Toby said.
"We know this isn't going to be forever so we are looking ahead to the next big thing."
The boys were coy about what they paid for the spinners but sold them for $10 each and said in some cases there was a 50 per cent mark-up.
They said the ones they purchased were of better quality than simliarly priced gadgets for sale in $2 style shops. Other retailers sold the spinners for up to $20.
Zephyr found the cheapest fidget spinner wasn't always the best value for money for their customers and the pair read reviews before placing an order.
"We didn't want to buy the cheapest ones out there if they were [bad] quality," he said.
"Some are a lot slower and a lot smaller than others so we look at all of the reviews carefully."
Zephyr's mother Angela Lovelock said the process had been positive with the boys feeling motivated by their success.
"They have seen that is it possible at their age to have their own small business," she said.
"It is not just about the fidget spinners but about how they can use what they have learned and look forward to the next big thing."
Zephyr has held the national snowboarding title for his age group for four years and Lovelock said he was always looking at ways to fundraise for overseas training.
"He has the nationals in Cardrona later in the year but in January he really needs to be training in Colorado to get more experience on the world scale."
The talented snowboarder is sponsored by Volcom and Burton but overseas travel required extra funding.
"The more money he can save the more training he can do," Lovelock said.
What is a fidget spinner
• The fidget spinner is a propellor-like toy with a bearing that sits on your finger and three weighted blades that spin around.
• Children can compete wtih each other, performing different tricks or keeping their spinner going the longest.
• While the spinners have been promoted as a "stress reliever" or a tool to help children focus, some schools overseas have banned them because they have become a distraction for students.