Nice setup. 50 gallons should be about right for one tractor and the ability to haul back and forth.
As far as filling at a gas station is concerned lots of trucks have a fuel tank / tool box that can't be set on the ground for filling. Pretty sure that rule is just for cans but I have filled cans on my tailgate on numerous occasions without encountering any intervention.
I have a 100 gallon aluminum tank from a Freightliner I bought from a salvage yard for $130. I use a 12V transfer pump powered off a deep cycle battery that remains charged by a solar panel on the roof of my barn. I added a mechanical gauge, shutoff nozzle, and water block filter. I'm all in around $300 not counting my solar setup. I have fuel delivered most of the time. I treat with
Biobor JF for algae and lubricity. Haven't had any problems.
I have a MEP803A diesel generator, JD 4310 and a NH575E backhoe in addition to my LX3310. I could use a larger tank. I was going through about 3 tanks a year when I was clearing land. Already had a 3 day power outage from the last hurricane this year. Will probably have to fill up once or twice more before the year is out. Hopefully not because of generator time. It burns about .7 GPH.
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