For Prime members only, Amazon offers a Crest 3D White Sample Kit
bundled with a $4.99 Amazon Credit
with free shipping
. (The credit is redeemable for select Crest and Oral-B products.) Assuming you'll use the credit, that makes the item essentially free and the lowest total price we could find. The items include a Crest 3D White 1-Hour Express Whitestrip treatment, Crest 3D White Radiant 2.5-oz. Mint Toothpaste, and Oral-B Glide Pro-Health Floss.