Want a hot deal for Doritos? Then head to Walgreens for a buy one get one free promotion. There is also a rare manufacturer coupon for Doritos, which makes these chips just $1.65! (Plus, spend $15.00 on select Frito Lay and Pepsi products and receive 3,000 Balance Reward Points.) Walgreens allows a coupon to be used on an item made free by a promotion. Keep in mind that this coupon can only be used once per customer. 

Buy 2 Doritos $4.29, sale price through 2/2
Buy One Get One Free through 1/26
Use one $1.00/2 – Doritos Flavored Tortilla Chips, 10 oz or larger, limit one per customer – (foodlionparties.com)
Final Price: $1.65 each, when you buy 2