I always ship to Canada with USPS; but due to the recent postal worker strike in Canada I decided to check out UPS. I was surprised that the cost was almost the same as USPS and shipping was quicker. There was a problem though. The customer in Canada emailed me that there was a "UPS Customs Brokerage Charge" Here is what he received--
Total Due (CAD):CA$36.86
Import ChargesGovernment Charges:CA$6.39HST or GST + PST:CA$2.13Other Government Charges:CA$4.26UPS Customs Brokerage Charges:CA$30.47Brokerage Fee:CA$26.50Brokerage GST/HST:CA$1.33Brokerage QST:CA$2.64
and I only declared $30 for the value...so the fees were more than the declared value

This is extremely crooked. I looked it up and UPS even had to settle a class action lawsuit because of this crookedness.
Long story short-- Never use UPS
