Assess your situation Track down the impacted drain and extent of backup Check if various drains are impacted (implies principal line issue) Hunt for visible drinking water destruction or overflow Simple Do it yourself Steps Pour boiling drinking water down drain Use plunger appropriate for sink/bathroom Check out baking soda https://www.kawatan.net/why-you-should-never-use-baking-soda-and-vinegar-to-unclog-a-drain/