Your results may vary and this is just a real world example of my experience today. I put a pair of wheel bearings and brake pads in the shopping cart. Shipping at $7.99. Added 4 spark plugs. Shipping upped to $8.99. Not bad. Figured I'll check filters. Add air filter. No change to shipping. Add cabin filter. Ditto. I'm replacing the transmission so the cooler in the radiator might be gunked up. Could flush but a new rad is pretty cheap. Add one to the cart. Shipping raised one buck to $9.99. Wow. A/C was blowing warm and I see junkyard markings on the condenser/drier. That is pretty cheap too. Put one of those in the cart. Shipping still at $9.99 and I check out before their computer changes it's mind. The $16 discount code more than covered the shipping. The key to keeping shipping costs down is to look for the delivery truck symbol in the search results. That indicates other parts that ship from the same warehouse as the first part you placed in the cart. So find and put the most important (expensive) part into the cart first. Then you have a choice of your second, third, etc. part that while not be your preferred brand, may still be satisfactory based on the none or minimal added shipping charge.