Arby's Roast Beef For 64 CentsWhen you “like” Arby’s on Facebook, you’ll have a chance to print a coupon that gets you a Classic Roast Beef Sandwich for just 64 cents. This coupon is only good tomorrow, July 23, and you must purchase a 22-oz drink to use the coupon. Still a great deal, because the whole thing should come out to $2 or less!