Sean Ross is a strategic adviser at 1031x.com, Investopedia contributor, and the founder and manager of Free Lances Ltd. Ariel Courage is an experienced editor, researcher, and former fact-checker.

If you’re shopping for a new dishwasher, you might be thrilled to save a few hundred bucks on a model you like during a big sale. But there’s almost no chance that you would buy the same dishwasher ...