Government charges are modest and are published: a fee collected at the border for the port-of-entry route, or a USCIS filing fee for a petition. Current amounts should be read from the USCIS fee schedule, Form G-1055.
Small fees, and the costs nobody budgets
For this classification the government charges are among the lowest in the employment categories, and there is little value in quoting figures that change; the fee schedule, Form G-1055, is the place to read them at the time of filing. What actually costs money is the preparation. Obtaining employment letters from former employers, particularly properties that have changed hands, takes persistence and sometimes a small fee.
A credential evaluation may be needed where the qualification was obtained outside Canada. Legal fees are justified where the credential relies on experience or the job title needs explaining, because that is precisely where a refusal is most likely. And a refusal at a port of entry has its own cost: rebooked travel, a delayed start, and an adverse encounter to disclose in future applications.