Growing up we had two of the 200 gallon tanks, one each for ORD and ORG. As we got to using less, the oil company stopped home delivery. So we took a fifty five gallon drum to them to get diesel, loading and unloading it and the pallet it sits on with the hay forks. My sister and BIL have been doing more farming than me, so they had the drum and hand pump at their place. I use three five gallon gas cans, buying ORD at our local bait shop. {you can pick up fifty crickets at the same time, and if you go fishing instead of mowing, you won't use as much diesel} One of the old ones, and two of the ones that don't work. The bad thing is the threads are not the same, so I can't put the good spout on the new cans. Until I learned to only put four gallons in them, I siphoned about half of it into the good can, then poured the rest without the spout. I do it free hand, and so far haven't spilled much.
When I was just using the B7500, five gallons would last forever. But since I bought the 6' RFM and have been using the 3930 more, I have been having to deal with it every two or three weeks.