Government fees on the current schedule are filed and paid by the petitioning employer. Which entity in the group bears the cost internally is a corporate decision, but the petitioner is the one on the form.
Separate the filing cost from the assignment cost
Hypothetical example: Government charges are set out in the published fee schedule and are revised periodically, so the current version should be consulted rather than a figure remembered from a previous filing. The larger costs in a process like this are usually internal: the time spent documenting a protocol that was never written down formally, retrieving payroll records for the qualifying year, and responding if a request for evidence arrives. Groups that expect to move several people benefit from documenting the process once, properly, because the same material supports later petitions. Relocation, housing and the family's own document costs sit outside the petition entirely and are frequently left out of the first budget.
Use the current published schedule for mandatory charges and identify any fraud-prevention or other fee that applies to this particular petitioner. Hypothetical example: A ceramic-tile manufacturer plans a customer-site deployment and assumes the customer will cover every filing cost. The petitioner remains responsible for presenting a truthful petition, and the contract should not encourage a description that hides who directs the work. Commercial cost sharing does not change the classification tests.
Confirm the fee rules before the petition is assembled. A cost estimate should not determine the employer relationship or the actual supervision described in the evidence.