An enforcement agent attends a home with property belonging to several people — how should ownership be established?

Scenario: An enforcement agent attends a home to recover a debt owed by one person. The home contains property belonging to several different people, including the debtor, their partner, and a lodger.

Question: How should ownership of the goods be established before any items are taken? What authority must the enforcement agent have, and what procedures should be followed? What rights do the non-debtor parties have to protect their property, and what remedies are available if goods belonging to a non-debtor are taken?