Where can I buy a teeth whitening product that won't eat away at my enamel, and also won't kill my wallet?

I can't afford going to the dentist, and I just want something safe, not too costly, and has been proven to work without unwanted or harsh side effects
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Go to your local drug store. Listerine has a mouthwash for whitening teeth. So does Crest and a few others. You swish it around it your mouth for a minute and spit it out. I have been using it and see a big difference.
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