Ziploc bags are buy one, get one free this week at Safeway.  You can combine that sale with the $1.00 off two Ziploc bag coupon from the 3/25 SmartSource and pay $1.00 a box after Catalina!

Buy 4 Ziploc Foods Storage Bags, 15-30 ct. $3.49, Regular Price
Buy 4, Receive $2.00 Catalina
Buy One Get One Free, Through 4/17
Use 1 $1.00/2 Ziploc bags from SS 3/25
Pay $5.98, Receive $2.00 Catalina

Final Price: $1.00 each when you buy 4

Note: Safeway will not accept a coupon for a free item. So you will need to purchase four boxes in order to use your $1.00 off two coupon.