Buying used, US to Canada, tax and duty?

I bought a NAD amp last year from someone in the US. Customs calculated GST on the Canadian dollar equivalent of the US selling price. There was no additional duty. This seemed interesting to me as I was under the impression that NAD was (is?) a British outfit. At any rate, being new to the whole "buying audio gear second hand via internet" game, I was totally unprepared for the whopping "brokerage fees" that UPS charged. From then on, I always requested USPS as the mode of delivery; if the seller balks at this, I walk (virtually speaking, of course).

Can someone please "clarify" outrageous UPS bokerage fees in dollars?

I've heard fees ranging from 18.00 for a grandmothers care package to 250.00 for audio stuff or automotive aftermarket motor parts/body kits. So I think it really does depend on the product/function and origin of manufacture..p.s. in one week I have never read so many negative experiences with UPS..my preamp is arriving USPS..

Chryslers_rule, my pre amp arrived intact, no brokerage fee, no 'duty' but I did get railed with BOTH gst and pst?? 103.00 plus the usual 5.00 handling bit..

I suppose they would charge duty + GST but on what amount?
The duty guys can't tell the value of the parcell unless there's a sales slip on it can he?

If the sellers says he sold it for 5.00$ plus shipoping, how could you get charged on a higher amount?