How do you go about shipping really big boxes? ...like Metroplex, For Max, and even the original G1 Fort Max? What does something like that even cost?
Sending or receiving? Anyhow, the answer is 'pretty much like any other package'. Make sure the item is properly padded, make sure the shipping box is large enough. Sure, the largest TF's are pretty big, but there are literally thousands of items that get shipped internationally every day that are way bigger than those TF's. I've had the big bots (including Fort Max, Brave Max and the huge official non-Transforming Scorponok figure) shipped to me from all over the world, especially Japan and the US, and there was never a significant difference except for shipping price. Depending on size and speed, large TF's will cost between €50 and €100+ to ship pretty much anywhere in the world. All postal and shipping agencies have online calculators or tables to check on costs based on weight and or size.