Promoters of a red glass exhibition centre for Takapuna have three months to sharpen a business case which calls for $5.3 million from ratepayers to get it open in 2016.
The estimated capital grant to a museum-grade exhibition centre is based on a $14.5 million staged project - with the rest to be raised from charitable and corporate sources.
The new figures for the project came as a shock to Devonport-Takapuna Local Board members.
Board chairman Chris Darby said yesterday that a more rigorous business case was needed to earn any level of ratepayer support.
"Also, probably the biggest risk for Auckland Council is not the capital outlay; it's always operating expenditure that needs year-after-year support."