FedEx has been the worst for me. About a month after you receive your delivery from FedEx, they send you an invoice for the tax, customs, and brokerage. This is of course all on top of the very-high shipping fee that you have already paid to FedEx. I get that tax needs to be paid, but the other fees are very substantial especially when considering that you already paid FedEx to deliver the part.

A recent example was me paying $70 for some differential parts. $41 to ship it to me was expensive but acceptable since I couldnt find anything in Canada. Approximately one month after delivery, I received an additional $41 invoice from FedEx. FedEx has now made more money from this sale than the company that I bought the parts from.

Larger companies (Amazon, Summit, Rock Auto, eBay) have "total cost" shipping options available where they will include the taxes, duty, and brokerage up front. The cost is always high, but at least you know exactly what your cost is instead of getting a surprise later on.