For EU Customers importing from GB. There are a number of issues to consider before continuing to trade.
Reviewing yours Product TARIC code to determine any licenses, certificates & regulations that may be required by the relevant departments (DAFM, HSE, etc.).
If your product requires a physical check, cost etc.
Discussing with your GB supplier the revision of contracts to include Incoterms
Reviewing the EU Commission guidance to stakeholders on the importation of your product.
This will establish who will act as the responsible person as importer of Record.
Once all the above are complete we can proceed to customs declarations for Importing and the chain of communication that must exist between Declarant, Haulier, Driver, Carrier & Revenue.
See attached information on importing by RO-RO, Air or LO-LO