Published filing fees from the USCIS fee schedule, professional fees for the petition, and the internal cost of reconstructing an employment and travel history, which for someone who has moved between countries is the largest unplanned item.
Reconstruction is the line item nobody quotes
Filing fees should be read from the USCIS fee schedule, Form G-1055, at the time, including any optional premium request. What is harder to anticipate is the cost of establishing a fact the company thought it already knew. Producing a defensible month-by-month record for an employee who has worked in two countries involves payroll extracts, contract archaeology, travel records and sometimes a request to the employee for personal documents. That is finance, human resources and management time. Legal fees reflect the same work, because the eligibility opinion depends on the timeline being right. Where the U.S. entity is new, premises and early hires are committed before any decision, which is a separate exposure and should be stated to the owners plainly.
Hypothetical example: Grant, a Canadian manufacturing executive, is offered a U.S. assignment that requires an initial petition and a later extension. His first review should distinguish mandatory filing charges from translation, corporate-record, travel, housing, and relocation costs. The petition forms and fee schedule settle government charges; a written mobility policy settles which business expenses the employer will cover. He should budget for maintaining evidence throughout the assignment, not only for the initial filing. A common problem is treating the extension as automatic and discovering too late that the U.S. operation lacks the payroll, contracts, or organizational records needed to justify the next stage.