Evaluate the specific situation Locate the afflicted drain and extent of backup Test if a number of drains are impacted (implies major line problem) Look for seen water problems or overflow Simple Do it yourself Ways Pour boiling drinking water down drain Use plunger suitable for sink/toilet Test baking soda https://www.kawatan.net/why-you-should-never-use-baking-soda-and-vinegar-to-unclog-a-drain/