Some places offer a break when ordering lots of 5 or 10. Maybe you can get with some of your other local arborilogicals and split an order.
Put a date on the packages and date the blade when you put it on the saw. And then mark the second or third to the last in the stack with "Time to reorder", like in the box of blank checks. Yes, it might be better on your shoulders if you changed blades a little more often since you now have some on hand.
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