Carol Lynch, a partner in the customs department of business consultancy firm BDO, said at the presentation of Bord Bia's Brexit Barometer in Dublin this week that while trading with the UK amounted to selling inside the same country under EU rules, a lot would change once it becomes a third country."Global companies already do it. Those who were around 20 years ago know it. It is doable, it's just a new procedure," Lynch said.