This issue is only relevant if your website needs communicate to EPOS one selling price for all countries, but to only apply VAT to those within the EU as a percentage of the selling price.

Example:

A £100 Product will be charged at £100 with no tax outside the EEC, although in the EEC it will include VAT

Non EEC = £100 Tax Free
EEC = £83.3333 + Vat = £100

Solution:
Tax is removed completely from Magento and the Juno integration will process the orders so that:
The Non EEC order will be sent to Visual as £100 with 0 Tax code
The EEC Order will be sent to Visual as £83.3333 with a VAT Tax code

Potential VAT Rounding Issue
“Whilst this somewhat resolves the issue this highlights the rounding issue that you will need to account for.

100 / 1.2 = 83.3333
83.3333 x 1.2 = 99.9999

Therein lies the riddle... and your accounts department will need to prepare for this “