Imagine a box or package whose dimensions are not a million miles away from a Fender hard case in a cardboard box. Doesn't matter what it really is, that gives you a decent steer as to what I'm talking about.
This box or package is in New York, in the possession of a well-known, reliable, and completely trust-worthy seller. This is someone I've dealt with before.
The seller provides an estimate of $800 - $950 to ship it to me in London. Bear in mind that the exchange rate today is £1.00 = $1.40.
Erm ... what? Shurely shome mishtake. That's enough money to buy me a return ticket from Heathrow to JFK and collect in person.
The seller checks, an replaces his estimate with an actual quote. The very cheapest he can manage is $733, which is with a UPS economy service. He sends me a copy of the UPS quote.
OK, that gives me everything I need to run the same request, but using the UK website for UPS of course.
So ... precisely the same dimensions & weight, the same origin and destination but flipped around so I'm shipping to him, and up comes a screenful of options using various UPS services.
The most expensive one there is £183, the cheapest is £135.
I take a screenshot and email it to the seller. The seller re-runs his own request and also takes a screenshot of his screenful of options. He sends me his screenshot.
The cheapest option is $733, the most expensive is $1200-ish.
That's the same package, being sent by the same courier firm, almost certainly on the same aircraft.
If he sends it to me, it costs me £524 (i.e. $733 / 1.40). If I send it to him, it costs him £135.
Only it doesn't cost me £524, of course. I have to pay 3.7% Import Duty on the entire cost of the package, including courier costs, so that makes it £543.
Only it doesn't cost me £543, of course. I have to pay 20% VAT on the entire cost of the package, including courier costs and Import Duty, so that makes it £652.
I can't help but feel that I must be missing something ...