Amazon has the 40-Count Hefty Ultra Strong 13 Gallon Tall Kitchen Drawstring Trash Bags (Blackout, Unscented) for $6.26 - 20% off coupon (first S&S order for this product) - 5% off with Subscribe & Save (cancel anytime) = $4.70 with free shipping on $25+ or with Prime.

Citrus Twist Scent and Clean Burst Scent are both slightly more with S&S and 20% off coupon.