Assess the specific situation Track down the influenced drain and extent of backup Test if many drains are influenced (signifies main line issue) Search for obvious water damage or overflow Essential Do-it-yourself Steps Pour boiling drinking water down drain Use plunger suitable for sink/bathroom Try baking soda + vinegar Option https://www.kawatan.net/why-you-should-never-use-baking-soda-and-vinegar-to-unclog-a-drain/