Evaluate the specific situation Track down the influenced drain and extent of backup Check out if a number of drains are impacted (indicates main line difficulty) Try to look for seen h2o problems or overflow Simple DIY Methods Pour boiling water down drain Use plunger suitable for sink/toilet Check out https://www.kawatan.net/why-you-should-never-use-baking-soda-and-vinegar-to-unclog-a-drain/