And how does it link to tax over BrickLink monthly fees?
If I understand correctly, it’s about income tax and about situations where
you (as taxed) need to prove you shouldn’t be taxed (or shouldn’t have been taxed).
For instance, your are a Portuguese resident but work for a company in France
and your salary is “income-taxed” directly / “at the source,” in France. You
need these forms to prove to Portugal that your income was already taxed, so
as not to be taxed again in Portugal. Or maybe reciproquely: to not be taxed
in France but only in Portugal as you don’t live in France (work remotely?).
(I’m not sure how that works / who should tax first (and only) / whether France
is a good example… but you should get the drift)
So I don’t see how this could apply to BrickLink, especially to the monthly fees
— Fees aren’t income tax.
— BL doesn’t collect income tax on them.
— You don’t pay income tax on fees. You deduct them from your income.
And, for that last point, it doesn’t seem to be about proving that you paid the
fees to be able to apply that deduction.
Portugal
France, Nouvelle-Aquitaine
If I understand correctly, it’s about income tax and about situations where