That's not a bad lot for a man who doesn't appear to have formal qualifications or institutional experience in his chosen field of foreign exchange.
But Robertson's fortunes have been in a funk since August, when authorities froze all of his assets and those of Prosper Through Trading.
The Financial Markets Authority, which is investigating the PTT Group, has serious concerns it was part of a fraudulent scheme designed to obtain money from the public, a High Court judge says.
While Robertson is not listed as PTT's director and holds a mere 1 per cent of its shares, he is thought to be the moving force behind the business, according to the same judge.
The complaint which sparked the FMA into action alleged Robertson was running a "Ponzi scheme", managing clients' money as an unregistered fund manager and not providing them with reports or returns.
Robertson has not responded publicly to any of these allegations and on Thursday said he could not comment to the Weekend Herald.
He is no longer in charge of PTT Group, which has been in the hands of court-appointed receivers John Fisk and David Bridgman since mid-August.
How PTT worked
PTT told budding currency traders they could "make money on a daily basis using our sophisticated software".
"We run the software from here and you receive a text alert when it's time to engage in a trade. It's easy we do all the work and you receive all the profit," its sales script said.
Potential clients, according to a receiver's report provided to the High Court last month, were led to believe that profits of up to $49,660 could be made from a starting amount of $2500.
Customers, some of whom paid thousands of dollars to receive daily alerts via text message or email, were set up with external trading accounts with the likes of CMC Markets.
Robertson, the receivers allege, was responsible for approving or sending alerts to clients, although PTT had no proprietary software for generating trading recommendations.
"Rather, alerts were sent to clients based on Mr Robertson's reading of news commentary ... and drawing on the opinions of other investment providers. The question therefore arises as to whether Mr Robertson had a proper basis to represent that such high returns were realistically achievable," Fisk's and Bridgman's report said.
The hard sell
PTT's lure of good returns certainly attracted hundreds of customers, one of whom told the Weekend Herald the company made persistent pitches to secure a sale.
"The phone just didn't stop," said the Auckland man, who paid PTT $16,500 last year but had more than half refunded after he complained.
As well as telling potential clients that profits were "large and instantaneous", receivers say the PTT sales staff had rebuttals ready for any who were not interested.
"For example, where a potential client makes a comment around trading being 'too risky' the answer the sales staff are to give include stating that risk is eliminated due to 'risk analysis'," they said.
"In an attempt to close deals, sales staff were encouraged to invoke urgency as a sales technique; for instance by saying 'we only have a handful left' or 'our boss has just told us that there are five left, closing on the next business day'."
Fisk and Bridgman, in their report, believe many clients may not have understood what they were being sold.
"Many clients believed they were 'investing' in the product with PTT Group and therefore should the product not work as suggested or not yield the profits promised they were entitled to request a refund of not only the initial up-front cost but any subsequent trading funds as well," the receivers said.
Robertson advised the pair that some customers may have been mis-sold investment packages by error.
Fisk and Bridgman also believe that shares in the group were sold, although Robertson said those that bought them were long-time clients or friends.
Millions came in
Just how many clients PTT Group has is still unclear. Robertson, in an affidavit, estimated there are about 460.
"We would ordinarily expect a business of this nature to have a reliable database recording client details and the specific products that have been purchased and the purchase price", Fisk and Bridgman said.
"PTT appears to have a paper-based record for each individual client. However, there seems to be no central electronic database containing all these details, but rather various Excel spreadsheets exist which outline various sales completed by a number of different sales staff over the years," they said.
Between 2013 and August 2015, the receivers estimate around $4.4 million was deposited with companies in the group.
About $1.9 million of this amount is thought to be from products sales.
The remaining $2.6 million includes loans from clients, proceeds of the sale of shares and money accepted for investment.
Despite the amount coming in, there was just $51,000 in company bank accounts at the end of August.
Fisk and Bridgman say they identified numerous transfers between accounts of PTT Group companies, Robertson and his wife Lisa.
Most, if not all, deposits transferred into the couple's personal accounts appear to have come from the firms in the group, the receivers said. Robertson, according to the receivers, said funds transferred to his wife were included as his drawings or were repayment of loans she had previously made to the group.
Down to $5000 a week
The asset freezing order obtained by the FMA captures the very clothes on the Robertsons' backs.
It also caught their multimillion-dollar home, a Bentley Continental, two Mercedes and an Audi at the couple's property.
Expensive watches and tens of thousands of dollars worth of jewellery are also on ice.
But the big ticket items are financed and it is thought the net value of all these assets is only $1.6 million.
When the freezing order was granted in mid-August, the Robertsons were initially allowed $1000 each week from their assets for living expenses and later another $1765 for mortgage payments.
When appearing in the High Court at Auckland, the couple's lawyer asked Justice Anne Hinton to allow a further $2300 each week for outgoings like private school fees, and finance on the vehicles.
Justice Hinton, in her decision last month, said some of these items in the Robertsons' weekly budget were "extraordinary" although she allowed the family a total of $4765 for expenses and their mortgage each week until December.
The family's home was the most valuable of the $1.6 million worth of frozen assets and the judge suggested it could be sold and its mortgage repaid. It was also suggested that the Bentley and one of the Mercedes could be sold, which could realise about $70,000.
Fisk said yesterday he was working with the FMA to apply for the assets to be sold.
What next?
Fisk and Bridgman last month recommended that four corporate entities forming the PTT Group be put into liquidation. While this has yet to happen, it is expected an application to liquidate the firms will be made.
The FMA, which said in August that PTT may be operating in breach of financial market legislation, could only say its investigation was ongoing.
However, to quote Justice Hinton, there are real concerns that Robertson and companies in the PTT Group "may have engaged in misleading and deceptive conduct, and misapplied funds accepted for managing on client's behalf."
"Civil claims by the companies, investors and/or creditors (and possibly criminal charges) may well follow," she said.
Past dealings
Robertson, originally from Britain, has been involved in a handful of New Zealand companies selling trading software. One, Russell and Brown Ltd, fell foul of the Advertising Standards Authority in 2008 after a complaint over a brochure for one of its products.
The ASA's complaints board formed the unanimous view that the brochure over-promised the size of possible returns in an unrealistic manner.
Russell and Brown was renamed Harrington Group that year and was put into voluntary liquidation in 2014.
Robertson, according to the receivers, was also associated with Morrison Ross, a company which sold software that gave suggestions on Australian Stock Exchange portfolios.
The company was wound up amid the tumult of the global financial crisis, with creditors claiming some $40,000.
