Hello, I have a situation here
* I have incorporated a Canadian company to conduct my independent consulting services.
* A US agency sourced a contract for me and the work is in Canada; i.e. for a Canadian client.
* The contract is between myself; i.e. a Canadian company and the US agency doing work in Canada.
* I will be paid in Canadian funds.
* I will submit an invoice monthly + HST (Canadian sales taxes) to the agency and they will direct deposit to my business account.
* I will remit the HST to the Canadian Revenue Agency (CRA).

My questions are:
* Do I need to fill up a W8BEN for this contract? My view is not but how do I fill up the W8BEN?
* How much (%) will be withheld from my payment?
* How do I get those witholding tax back since it is part of my Canadian Corporate revenue and I need to corporate tax return to CRA.