I did the dirt prep work for both my pole barns. What you need is a rotating laser. I bought a DeWalt laser, tripod and stick with a detector for around $800 about 20 years. I used my Ford Jubilee with disk to break up the sod and my little terramite to move the sod to a compost pile.
I built 30x40 pole barns, If I did the math correctly every inch the grade is off is 100 cubic feet of concrete. 27 cubic feet is a yard of concrete. A yard of concrete costs about $100. So, it doesn't take long to pay for a rotating laser level. After I got the ground laser level, it takes a good rain to settle the dirt. I used my 5000 pound roller to pack the dirt. I hired a good friend and concrete finisher to put down a 6 inch floor with wire after the pole barn was built. He used a Georgia buggy and my rotating laser to set the concrete grade with. I have yet to have any of my concrete finishers work crack or settle. Both floors were a continuous pour, The only forms were the boards on the side of the pole barn. Don't go cheap on the floor. My concrete finisher won't use concrete with fiberglass or rebar. He only uses wire.
Make sure the pad of your barn is the highest point so rainwater will run away not towards the barn.
I wanted to build a pole barn on an empty lot next to my house.
Area planning said no pole barn unless there is a house on it.
I had my empty 3/4 acre lot attached to my houses lot.
So do your homework before building.
I know a man who didn't do his homework and was forced to remove his pole barn after it was built.
Talk to your county assessor first, I wanted a bigger pole barn than a 30x40.
The assessed value of a large pole would cost me more in property taxes than my 3 bedroom brick 2000 ft house with basement and 2 car garage.
I settled for going taller and adding a loft. I use my Kubota to lift objects to the second floor.
That cut my property taxes in half. Go taller vs bigger.
If I had it to do again, I would have gone 14.5 feet vs 14.
I strongly recommend having vented eaves, ridge vent, and clear siding under the eves,
The Amish built this barn in 2 days. The cost in 2019 was $16500 without the floor. I did the wiring.
Please do your homework,
View attachment 115284 View attachment 115284