I use a postage scale to weigh packages beforehand, and then I go to the appropriate site (such as UPS or USPS here in the states) and use the postage calculator there to figure a price for the physical size and weight of the package going from my own location to some far-away location still on the continent ... and then I add that amount to my beginning bid or buy-it-now price and make my eBay listing with "Free Shipping". At that point, my shipping expense is covered without regard for wherever the package might eventually go. Along with all of that, however, I typically add a note for any possible international buyer that an additional amount will be required for international shipping.
The last I knew (at least here in the states), eBay charges its seller fees based on the entire amount of the transaction, including shipping, and that means a seller no longer saves any money by *not* offering free shipping. So, and again: I just offer free shipping while knowing I have my greatest possible expense covered in the overall beginning bid (or buy-it-now price for an outright sale).
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I began looking for someone like me when I was five ...
My search ended at 59 ... right here on WrongPlanet.
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