Many supporters are concerned how United will be able to afford to service the current debt. It has been suggested the repayments alone will rise to £50m a year following a refinancing move last month that added another $125m (£93.4m) to the amount owed.
At a time when transfer fees and wages for elite players are spiralling, some supporters think the stadium will have a negative impact on performance on the pitch.
"There's not a price," said Roche. "I can't go and get a quote on this right now. We have to go through the design process. It's not helpful to suddenly throw a figure out there.
"We've still got all the funding options available to us. We can have debt, equity, shares, other investors. We've had a lot of approaches as you'd expect. A few people are saying, 'I want to be part of this. Can I be part of this?'
"We are not worried about the level of interest. We need to know how much it's going to cost and then what's the best way to pay for it."
Roche conceded it was possible for the costs of large-scale infrastructure projects to spiral "out of control" but pointed to the £50m upgrade of United's Carrington training ground - delivered on time and under budget in August 2025 - as evidence of financial discipline at the club.
"People said you're never going to do that - but we did," said Roche.
Roche was flanked by Trafford Council leader Tom Ross.
He said no matter who wins the Greater Manchester mayoral election on 30 July, the project would proceed as planned: "The new mayor will be able to sit in the meetings, but not be part of the development corporation itself."
Ross also said talks would continue with Freightliner over the land United had hoped to use for their new stadium before switching as talks around costs stalled.
The land remains integral to the wider regeneration project.
"The aspiration was to explore having a stadium on Freightliner but in terms of land assembly, the new stadium will be in the right place.
"As an area development corporation, we have to explore what can be done with the Freightliner land and the wider discussion around the whole strategic train network. But that's not for now. That's a longer-term conversation."
United chief executive officer Omar Berrada was also at the event. Roche played down hints made by Berrada in the United States last month that the project may not proceed, saying "we've gone so far".
And she is adamant no public money will be used for stadium construction.
"That's not something that we ever wanted to do or thought about," she said.
"We, as a football club, need to stand on our own two feet. We need to pay for our stadium for a whole host of reasons.
"However, this project is massive. It's a lot bigger than the stadium. What we can't do is pay for a new train station or new infrastructure. Our funds will go on the stadium."
