The key that grocerysmarts.com uses is combining manufacturers coupons with sales, and store coupons too, where possible. That way the item is already on its best price when you use a coupon on it to get it even cheaper.
I just started getting the newspaper on Sunday, so my coupon inventory isn't huge yet, but I decided to start with Walgreen's since they have their own coupons from their ad, take manf. coupons/ printables, and have a monthly in-store coupon book. You can use up to 3 coupons ON ONE ITEM THERE! I just made a quick list from grocerysmarts and headed out to try it. HOLY CRAP! IT WORKS!!
I paid in two separate transactions because the Pepsi gave me a $5 coupon for my next purchase, and there were a few other things that had limits, so I broke those into two groups. Here's what I got:
5-12 packs Pepsi, 4 boxes Kleenex, 4 rolls Bounty paper towels, 5 pkg Halls cough drops, 4 cans Glade air freshener, Lysol toilet bowl cleaner, Lysol wipes, 2 boxes Fiber One bars .
For all of that I paid 34.47 and saved 35.04 off their regular prices!
They were out of a few other things, so tomorrow I will go back and get (or demand a rain check for) Oust Air sanitizer for FREE, Scrubbing bubbles flushable wipes for .89 each, and Fantastik cleaner for .89 each. Yeah!!
In case you are wondering if it was hard or time-consuming, I was in and out in 20 minutes (because I actually had and used a list) and I had my 4 and 2 yr old with me. Easy peasy lemon squeezy!