Sure of his facts with a mind for figures, Mr Malkin told the conference he met Prime Minister John Key to talk about rebuilding Christchurch as an eco-friendly city.
The man from Manhattan plans to spend more time in New Zealand because he is developing a southern house and brought to the summit two Wanaka architects, Anne Salmond of Salmond Architecture and Sarah Scott of Sarah Scott Architects.
Mr Malkin referred to his "personal project" in the lakes area.
He is president of Malkin Holdings of One Grand Central Place and the business spent US$550 million ($730 million) refitting and refurbishing the Empire State Building as a world leading light in environmentalism.
Mr Malkin spoke to property managers, agents, landlords, architects, surveyors and valuers, telling in detail about changes to Manhattan's signature office building which draws 3.8 million visitors a year.
Former US President Bill Clinton praised the skyscraper changes, which included the retrofitting of all its 6514 windows.
An article in Queenstown's Mountain Scene newspaper, headlined "Polytech sugar daddy a Big Apple Greenie", referred to a deal between Mr Malkin and Otago Polytech. Mr Malkin gave the polytech a "substantial ... there are five noughts on it," donation, according to Phil Ker of the Polytech.
But Mr Ker said this month he was unsure exactly where that deal was at.
"Tony has disappeared off our radar - we do not know where things are now at," he said.
And Queenstown sources said no house had been built at his property.
The Empire State Building initial public offering could raise US$1 billion on a building which Tony Malkin's father, Peter Malkin, bought 10 years ago from Donald Trump and a business partner for US$57.5 million.
Malkin Properties has a long list of Tony Malkin's achievements, saying he "is a member of the Urban Land Institute, the Real Estate Roundtable and chair of its sustainability policy advisory committee, the board of governors of the Real Estate Board of New York and a board member of the sustainable forestry management company Greenwood Resources, advisory board member of MissionPoint Capital Partners, member of the Committee Encouraging Corporate Philanthropy, member of the Advisory Council of the NRDC's Centre for Market Innovation, and member of the Advisory Council of the Harvard Stem Cell Institute"
ANTHONY (TONY) MALKIN
* New York
* Family business owns Empire State Building
* Engaged architects for Queenstown house
* Spoke last year at Green Property Summit
* Made big donation to Otago Polytech
* Wants Christchurch rebuild to be eco-friendly.