It is the first Wellington property to win the Supreme Award in five years.
The company agreed to sell its 171 Featherston St building to an undisclosed party for $76m.
Fran Wilde has another couple of weeks as chairwoman of Wellington Regional Council.
Hugh Pavletich also points to the Auckland merged supercity and the disappointments and rates hikes.
The sale is expected to be completed in early August.
"Supercity dumped. Batcity and Spidercity still possibilities."
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