Architects don’t determine budgets alone
The construction manager petitions the architect as the owners rep for change orders for cost increases
Unless things have changed since last time I built a property from dirt up
2009
And builders or construction managers here?
Present and accounted for.
The numbers published for media (and often times investors) consumption is rarely the real data on mega projects (Think about the "big Dig"). I have been the Senior Project Manager on a large development project and seen how the games work. I can, and have reported, the forecasted cost of a project (usually including the latest change requests from the "owner") one week and then get a copy of the report sent to investors that does not reflect the numbers I report. They usually report lower projections than I report to them. They will make it up in VE (Value Engineering) - lol.
It is important to realize that "investors" can mean different things depending on how a deal is structured. In the Middle East, for instance, the controlling money (usually royalty) is reporting the risks and rewards to the other legally invested parties. They do not want it to be known that the project is "forecasted" to be 20% over budget before the first shovel of dirt is turned. There are companies that are invested and bad news affects stock prices, bonuses, careers, etc.
In my career, have been asked by owners to modify books and reports to them, for them, so they don't have to report bad news. It gets harry when you have to keep two sets of books and make sure the "owner" is legally bound to both.
When I do have control of the budget (as the owner of a building or development), I put gross costs out to those who need to know including TOTAL investments (land, construction, equipment, technology, etc.) so high that interested parties KNOW it's inflated on account of business confidentiality. Then the parties at risk get their own accounting of where we are. I don't play these games. That said, I do not often work with government money and not on projects of the scale in this story. (In the case of the Middle East - Royal Money equivalent)