When checking prices, remember to keep track of shipping costs, if you order from a number of places to save a few dollars, usually your shipping costs will eat up those savings and in the long run cost you money. Also order in quantity, if you think you will need 20 this year, order 25. Don't order 2 or 3 at a time, try to forecast your needs for the long term. Those shipping charges add a lot of cost to your product, so maximize your orders.
Marvin