Government fees are modest and set out in the USCIS fee schedule, Form G-1055, for a petition, or collected by CBP at the port for an in-person application. The real cost of a delay is repeated preparation: a reissued letter, a second review of the duty description and, if a refusal has already happened, the effort to overcome it.
Budget for the second attempt, not just the first
Applying at a port of entry is inexpensive at the moment of decision, and a petition filed on Form I-129 carries the USCIS fee plus premium processing where the employer wants speed; the fee schedule changes periodically, so Form G-1055 is the only figure worth relying on. Around those numbers sit costs a delay multiplies. Each reissued offer letter takes employer time and, sensibly, a review by an adviser.
A transcript ordered for the first attempt may need reordering. If a document is not in English, a complete certified translation is required. Travel to a port that turns out to be premature is wasted.
Above all, a refusal recorded because a stale letter no longer matched the job is expensive in a way no fee schedule shows, since every later application answers for it.