I'm missing something... if you use about 5 gallons a week to mow six acres why are you buying 500 gallons of diesel at a pop? I mow about ten acres with about 10 gallons but can't see how buying bulk would benefit me. I mow at most once a week and the growing season here is from about early June through early October, but there are weeks in the beginning and end when I don't need to mow or it's too wet to mow.... and most years there's a short drought lasting 3-4 weeks when the lawn doesn't grow enough to mow. So if I mow 15 times a year that's maximum... that's about 150 gallons of fuel. And during winter I use 5-8 gallons to plow my driveway. What are you doing with 500 gallons of diesel on just 6 acres?