The average is between 1000 to 3000 CAD

For representation of counsel in Canada (best to have a Canadian lawyer on this) the average cost, in Canadian dollars, would be anywhere from $4,500 to $7,000, for a skilled, independent worker to seek immigration.

There are some extra charges, however, since immigration officials usually require an Arranged Employment Opinion, which is something a skilled, experienced immigration lawyer can draft for you. It takes a lot of work and research, and usually will be billed at an extra $1,500 to $2,000 in Canadian dollars.

Finally, there are the application fees themselves, set by the government. The attorney usually drafts the application for you, and will add in these fees on the legal fees bill as a separate item, usually around $400.

All of this will help you to file the best application possible. A good immigration lawyer also would be able to give you valuable advice concerning occupations that are eligible for immigration streamlining, and how it's best for you to go about proving that you qualify for this.

Just so you know you do not need an attorney to immigrate to Canada, my husband did it without one.
You can apply for a work permit even if you do not have a job lined up, however if you do have a job lined up it is to your benefit.