In 2007, he featured on the NBR Rich List with an estimated fortune of $60 million.
However, after borrowing $7 million from state-owned Kiwibank, Mr Ha could not repay his debts.
Receivers took control of Don Ha Real Estate's properties and assets in March when he could not pay his multimillion-dollar debts to Kiwibank.
The portfolio including, several 2-4 bedroom houses and two 10-bedroom boarding houses, is being marketed by Bayleys Real Estate and auctions for the properties will be held on November 30.
It was "one of the city's biggest residential portfolios to be brought to the market in recent years," said Bayleys residential mortgagee manager Hayden Butler.
President of the New Zealand Property Investors' Federation Andrew King said the mortgagee sales served as a warning to potential investors seeking advice from advertised 'mentors'.
"A mentor is someone who helps the individual achieve the results they want to achieve and I don't think many people want to achieve bankrupcy," he said.
Some mentors were high risk operators , which has been a "plague" in the industry for several years, said Mr King.
He believed Mr Ha should not continue to give others advice.
"I wouldn't think it's ethical for someone being forced to sell rental properties to continue doing it."
However, Mr Ha disagreed.
While his mentoring programme had ended and he was focused on buying and selling real estate he had plans to develop his coaching in the future - and his experiences made his advice more valuable, he said.
"I have something big for mentoring in the new year but I can't say what it is - it will be worldwide. The experience is everything," he said.
"I've got more people coming to me now for advice now that I've been through it. I would say I'm more sought after.
The forced sales were an opportunity to "help me restructure my business plan", said Mr Ha.
Mr Butler said the portfolio was accumulated over several years and Mr Ha had looked for homes close to parks, reserves, sports amenities, as well as employment and transport infrastructure.
Eight of the homes have tenants and one is vacant.
It was difficult to put a value on the properties, said Mr Butler : "We're asking for the purchaser to tell us what they're worth".
As part of the mortgagee process, all tenancy rentals have now been benchmarked against the market and have been shown to be delivering solid returns, he said.
Mr King advised people wanting to learn about real estate to read relevant books, join an investors' group and if paying for mentoring advice, to look for someone with extensive experience in the industry.Richlister
