Craig Kirrin Gore, 53, was found guilty in a judge-only trial of dishonestly gaining almost $350,000 from self-managed superannuation funds involving Arion Financial in 2013 and 2014.

He was found not guilty of five related charges.

Gore, son of deceased Gold Coast developer Mike Gore, promised investors the money would earn more than eight per cent interest for short-term investments in debentures to be repaid to their accounts within three months.

However, it never happened - Gore invented excuses for staff to use when investors requested their money back.

In a sentencing hearing in the Brisbane District Court on Thursday, Judge Michael Byrne said Gore was aware of the poor combined financial state of Arion Financial and Arion Group when he exploited the "trusting nature and vulnerability" of his victims.

Gore knew there was "no real prospect of paying interest or repaying the capital" at the time the funds were invested.

"You personally made contact with the director or directors of the complainant companies and induced the complainants to make investments which I have found, in reality, were really unsecured loans," Judge Byrne said.

"'These offences have as their genesis or desire on your part to get a new business up and running."

But Judge Byrne found Gore made no effort to repay the investors who were trying to prepare for retirement when lured into the scheme.

"Self-managed super funds are a legitimate investment vehicle," he said.

"The very fact that your conduct was targeted at people who were legitimately trying to save as much as they could both by way of investment and necessarily for retirement is an aggravating feature.

"The complainants were not people who were throwing money recklessly at obvious get-rich-quick schemes that were always doomed to fail - they impressed me as people who were trying to make sensible decisions as to the responsible investment of their assets."

The court found Gore's conduct to be "deliberate and targeted", and there was no evidence of remorse from the former rich lister whose fortune was valued at $183 million in 2007 in the BRW Young Rich List.

Gore will be eligible for parole after serving two years' imprisonment.

Australian Associated Press