He said the Auckland Council-controlled organisation had been a generous supporter, charging Team NZ a "super peppercorn" rental for the last six years for its Viaduct Basin headquarters.
But with the site to be bulldozed for a multimillion-dollar development, the syndicate would have to pay market rates at the alternative site near Westhaven Marina.
"To be honest [my board] has lost our enthusiasm for generosity in light of what seems to be the Government not stepping up. If they do move the board are willing to house them again but it might not be on a sweetheart deal like before."
He said Waterfront Auckland had every reason "to play it a little more carefully now".
"This is a major investment so we're taking a very serious look at what we'll be getting into before giving them another free go. I can't be more honest than that."
Public sentiment is also against the sailors, who last year blew a commanding lead against Cup holders Oracle in San Francisco. A Herald online poll opposed splurging more public money on chasing the Cup, with more than 80 per cent of the 5,500 voters against further taxpayer investment. The Government has already given $5 million in bridging finance to Team NZ, but Economic Development Minister Steven Joyce said it wasn't fair for taxpayers to carry the full risk of the challenge.
"We've said we're happy to consider a case to be a sponsor but it's not going to be a Government-led challenge.
"It is time for a bigger contribution from the private sector," he told the Herald on Sunday.
"If everybody else is turning up I'd be happy to go back to my colleagues and look at an additional $2m-2.5m, but certainly not the $5m they requested."
However, opposition politicians, tourism bosses and maritime industry experts believe a decision not to invest would be disastrous for New Zealand.
Marine Industry Association boss Peter Busfield said it would be a significant loss to the New Zealand economy if Team NZ folded.
The America's Cup served to promote New Zealand as an incubator of cutting-edge design.
"If New Zealand doesn't enter a team it will take away the incentive for other teams to have their work done in New Zealand."
Busfield said the event ticked all the boxes for profiling New Zealand as a place "for design and innovation, beautiful coastlines, nice people and a great place to visit for business or pleasure".
An evaluation of the economic benefits of the 2013 America's Cup to New Zealand found that from a $36m investment, the domestic economy received an $87m boost.
Fiveways to raise the cash
• Lotto. Powerball has jackpotted to $5m.
• Hold a Telethon.
• Go cap in hand to Coatesville. Dotcom-Team NZ anyone?
• Ask Michael Fay to get his cheque book out again.
• Have a whip around the senior Team NZ members. They have property portfolios worth millions.