Crest mouthwash is on sale for $2.99 at Walgreens. Buy four bottles and earn a $6.00 Register Reward. Stack four $0.50 printable coupons with a Walgreens Points Booster coupon. Find the Walgreens coupon on the front page of this week’s ad. Keep in mind that the printable coupon is for the Scope variety only. The final price will be just $0.85 each!