IS BREXIT COST OFFSET by the BRENTRY COST ?

When Britain was finally allowed to join the EU in 1980 what were the conditions of that ENTRY ?   Also what was the Financial COST to Britain of any EU conditions Britain was obliged to assume ?

Now that Britain wants to leave all that is ever highlighted is the cost suffered by the EU because Britain wants to leave !

Has the latent cost which Britain assumed on its BRENTRY to the EU been calculated and offset in the BREXIT cost now being discussed ?

This benefit to the EU countries that remain, never seems to be highlighted after any Discussions or in any Press Articles !

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