Do I need a waterproof lantern or just water-resistant?

For most car campers, an IPX4 or IPX5 rating is sufficient — it handles rain and splashes. IPX7 (full submersion) is overkill unless you're paddling or expect the lantern to be dropped in water. Reviewers across the candidate set rarely cite waterproofing as a real-world failure point at IPX4 or higher.