They can’t pass on the costs of any issues to Everton, apparently, under a fixed price contract
They haven't signed a fixed price contract. This all stemmed from an email Baxendale sent to fans which mentioned them having clarity of costs. From this their fans have run with it being a fixed price, which has then become truth somehow.
"I am delighted to tell you that we have finalised and signed a contract with our construction partners, Laing O'Rourke, which gives us greater certainty as to the costs of the remaining stages of our stadium project. The agreement ensures the work on bringing our new home to reality will continue apace.
To explain the significance, this agreement means we have renewed clarity over the costs for the remaining stages of the project - and that clarity is in line with our budget and cost planning. In short - we have certainty in these uncertain times.
Our accounts, released last month, revealed the profound scale of the impact the pandemic has had, and continues to have, on our Club. They also demonstrated, though, the scale of investment we have already made in our new stadium - and the unwavering commitment of our owner to finish what he has started.
To put it into financial terms, this is the biggest investment and the biggest commercial deal and partnership we have ever struck in our Club's history."