Pensioner Mary Boyle has forgiven Steven Robertson since he repaid $29,000 she had handed over for a gold trading investment.

But she does not think of him fondly.

"I don't know how on earth he lives with himself," she said.

Tim Hunter The unmarked office of Prosper Through Trading, or PTT, in a strip mall at Kumeu, west of Auckland.

Boyle, a retired teacher in her 80s, became involved with Robertson after a brochure landed in her letterbox, followed by a phone call from a company called PTT.

It was a sales pitch for a gold trading scheme called Prosper Through Trading.

"Gold is a solid investment in today's climate," it said. "With PTT, a renowned market educator by your side, you will succeed."

A graph depicted apparently soaring profits of 2000 per cent in less than six months.

Although she was not wealthy – she lived in a council flat – Boyle had some money available and decided to give it a go.

"I knew it was trading in gold, because the brochure said so. And you buy a licence to operate on the CMC platform in order to do your trading. I've still got that ... It cost me $4000."

The idea was to set up an account with CMC Markets, whose online trading platform allows buying and selling of derivatives linked to currencies, commodities and shares.

PTT would provide text alerts on when to buy and sell gold.

"They took my cellphone [number] and they tell you to buy gold at – and they give a price.

"Then a little while later you get 'sell gold' at such and such a price. It comes as a text message."

Boyle says she was given instructions over the phone on how to use the CMC software, but couldn't make it work.

"I tried to," she said. "That was where I had this row with Steve [Robertson], because I had this lesson and I tried to do it, and it wouldn't go through. You have to do certain things and I did it wrong. I wanted to ring them back and ask what was I doing wrong.

"And they would never answer the phone and they would never ring back."

It appears that Robertson then offered an alternative scheme – as Boyle understood it, she would pay money directly to PTT who would then invest it on her behalf.

On April 14, 2014, she paid $10,000 to PTT, followed on April 16 by a further $10,000 to Maxwell Foster, a company directed and owned by Robertson.

"Right from day one I kept asking for documentation so that I could prove I had paid him $20,000. And he would always say 'yes yes I'll do it you'll get in three days'. I did that for six months."

Meanwhile Boyle was asked for a further $5000 for "computer software", which she paid in July.

By September Boyle still had not been given any documentation and demanded a refund, whereupon in October she was sent backdated documents describing her $25,000 as one-year loans to PTT at an interest rate of 17.5 per cent.

At that, Boyle called her lawyer in Hamilton, who pressured PTT into paying a refund of $29,000 plus interest.

PTT's brochure and website provide no physical address details or information about who is involved with the firm. They give its addresses as a PO Box in West Auckland and a virtual office service in a Sydney office tower.

The Companies Office registers PTT's sole director and shareholder as Sharon Lawson of Kumeu.

However, inquiries by Fairfax found the "renowned market educator" operates from a small unmarked unit in a strip mall at 190 Main Rd, Kumeu, the same place as a previous entity run by Robertson called Harrington Group.

Harrington, which offered a text alert trading scheme for foreign exchange, was liquidated in December.

Both Harrington and PTT took advantage of a trading platform provided by CMC Markets, a London-based company offering contracts for difference – a type of derivative that trades off changes in price of an underlying asset.

CMC said its trading software is available at no charge to clients and expressed concern that Boyle appeared to have been charged $4000 to use it.

"The company does not condone any third party representing that a licence fee is required to use the CMC Markets platform."

It said it had "no official agreement with the company [PTT] or their directors", but "can confirm it will be further investigating the actions of PTT".

Robertson did not return calls seeking comment but sent a statement by email.

" Mary Boyle bought software based products from our business earlier in 2014," he said.

"At the time the sale was made she appeared motivated by making a financial return. She subsequently advised that she was having difficulty in using the programme.

"Following this advice we entered into constructive discussion with her which saw us returning all money she invested with us in November 2014, plus an additional 17.5 per cent per annum extra that her investment produced over a 6 month period.

"Given that this matter has been resolved to Mrs Boyle's complete satisfaction we do not believe there is anything else to say."

Investment schemes such as PTT's do not appear to be subject to regulation by the Financial Markets Authority, although last October it issued general advice that investors should take extra care when dealing with "offers involving software or so-called 'trading systems' – often for forex trading – where consumers must buy a licence or software, in order to participate."