ATT, 200 minimum trade in value with purchase of S8/S8+
If you are purchasing an S8/S8+ from ATT, be sure to get a promo code for their trade in promotion. Any phone valued over 20$ should be bumped up to 200. Stackable with the BOGO if you have directv and add a new line.
Not sure yet if it stacks with the existing Costco/Best Buy etc deals.