The issue of establishing a presence in the other jurisdiction is generally more relevant to service providers rather than to Sellers of goods. Sellers of goods can manufacture or procure their products within Northern Ireland and establish a satisfactory means of delivery of those goods into Ireland. The goods may be sold through shops within Ireland and therefore the origin of the manufacture of those goods is not that important.
However, a service provider will be providing a personal service and, as such, his presence and identity to the client are more important. The advantages of establishing a presence in Ireland is more direct access to that market. Where you don’t establish an actual presence, you are relying on the integrity of Sales Agents, Distributors and Couriers/Transport Agents.
It is difficult sometimes to convince buyers/clients that you are in a position to provide an effective service within that jurisdiction where you do not actually have a presence in that jurisdiction.