Separate official procedure charges from transcripts, evaluations, translations, travel, and professional preparation.
Spend on evidence, not on assumptions
Budget in three columns, because they behave differently and are often paid by different people. Official charges come first: check current amounts on the USCIS fee schedule, Form G-1055, and on the relevant port-of-entry and consular pages, since figures quoted elsewhere go stale. A Canadian citizen ordinarily presents the application at a port of entry, which carries its own processing charge; an employer that files Form I-129 instead pays the petition charge and any optional premium processing it elects.
The second column is evidence preparation: transcripts, a licence certificate in good standing, certified translations, and a credential evaluation where the degree was issued outside Canada or the United States, which is frequently the largest single line. The third column is business and household spending: travel, temporary accommodation, insurance, and covering Canadian work while away. Agreeing in writing who pays which column prevents a dispute later.
Nothing in any column improves eligibility. A paid evaluation, an expedite fee or a booked flight is spending, and it cannot supply the applicant's Canadian or Mexican citizenship, the schedule entry the work falls under, the credential that entry requires, the written prearrangement, or compliance with the bar on serving a wholly owned U.S. business.
If cost pressure is shaping the evidence, get a U.S.-licensed immigration lawyer's view before spending.