First, shipping out of the U.S is expensive. Usually the ebay sellers use ebay's postal calculator which seems to be a bit skewed....read alot.
If shipped by USPS (postal service) you may end up paying pst&gst as well as 5$ canada postal charge. Although in many cases it will arrive and you end up paying nothing at all. Depends on the value in most cases. New or used does not enter into the equation.
If shipped by UPS/Fedex/DHL you will pay the ebay sellers postage as well as the brokerage fees, pst and gst as well as any other fees they dream up. So AVOID at all costs.
One plus about UPS etc is that things get here quicker although not in any better shape.
My personal method of choice is to have it sent to a postage outlet in Sumas Wa. called Ship Happens. They will hold it until I am able to come get it or arrange for a buddy/relative/acquaintance pick it up for me. And they only charge me 5$ per item.
I agree with this post completely. Avoid shipping with anyone else but USPS. Very rarely, and for some unknown reason, you will be asked to pay PST & GST. No rhyme or reason when or why, but occasionally. The worst ever for me was UPS which sent a bill for brokerage for $64. I ignored it. You have to be disciplined and just say "No" to the sellers if they will only ship FedEx or UPS.
I have used Ship Happens once, but it was for a large order (frame, oil tank and fenders) which could not be shipped by mail. Ship Happens is great except I had to deal with power mongering, low self esteem boarder guards ... on both sides.
Peace & Postal, Dennis