Assess the Situation Identify the affected drain and extent of backup Examine if several drains are afflicted (suggests main line challenge) Try to find obvious water problems or overflow Fundamental Do-it-yourself Steps Pour boiling drinking water down drain Use plunger suitable for sink/rest room Try out baking soda + vinegar https://www.kawatan.net/why-you-should-never-use-baking-soda-and-vinegar-to-unclog-a-drain/