"Even its 'worst case scenario' deduced the centre would break even and pose no ongoing running costs for the Whangarei District Council and ratepayers," Mr Guy said.
The trust believes that the 300,000 visitors annually stopping in Kawakawa to view the town's Hundertwasser toilets point to success for the Whangarei project.
Trust member Ian Reeves said the NRC conversion would result in the last authentic Hundertwasser building in the world. It was supported by iwi and, as well as Hundertwasser art, would host the sole, curated gallery in New Zealand dedicated to Maori fine art.
Three other building proposals are under consideration - an Arts Maritime Play (AMP) proposal plans to exploit the site's location, maritime heritage and local relevance.
It would be known as the Voyaging and Visual Arts Centre and create multipurpose spaces inside and outside, some commercially operated, reaching along and even into the Hatea River and into the city.
A Harbourside proposal - whose backers include former councillor Wally Yovich - is full of "firsts" and would house Whangarei Art Museum, freeing up that building for other public use. The building and surrounds will host and collaborate with a number of creative disciplines, including music, writing, film and digital. It could be open in 15 months.
One of the backers of the third proposal, engineer Peter King, this week said his proposal was conceptual only and he supported the revised Hundertwasser proposal.