In my experiences, the "Final Bid Fee" is like their "commission", and "Size Handling Fee" is for shipment from the YJA seller to BIDJDM's warehouse. I could be wrong, toss them an email to make sure.

You authorize BIDJDM to charge your PayPal through your "agreement" if you win. If you win, you'll be charged through PayPal that moment. The storage fees are also set up as "agreements," they'll be charged to your PayPal on the days noted below.

You've got a total of 15 storage days, 5 free and 10 paid. On day 6 you'll be charged and you'll have until day 10 to ship. Day 11 you'll be charged again and have until day 15. Day 16 they'll consider it abandoned. If you win multiple options you can have them group them all together, provided that the last item makes it in before the first one's storage period ends.

I had to pay customs to on one previous order (strut tower bar, steering wheel, and some horn buttons, IIRC) but that was through FedEx. I think it was because of the total amount of crap I purchased. I've noticed that I had to deal with customs with FedEx and not with packages sent through EMS.

Canada Post? I'm about 2600 miles to the SW in California. I have to deal with USPS. :P