If you want to buy good oil cheap for your Business the best way is to buy it by the gallon or bulk.
Just so you know buying by the 2.6oz bottle of Echo oil (Using HD price) your paying $2.97 per bottle or the equivalent of $145.53 a gallon. You can buy a gallon of the Echo Power blend for like $40 a gallon. The Stihl I just picked up was $52 a gallon, and both will make 50 gallons of mix. I do the same thing with oil filters that cost $11.95 each, if I buy by the case I can get the same filter for like $6.00 each.
When your running a business buying smart when you can, getting discounts from a dealer all can effect you bottom line.