Anyone lay their own concrete?

Hey FABO. I’m planning a 40x48 pole barn shop. The total amount was a little crazy so I’m looking for ways to save. The concrete alone was quoted at about 12k (includes forming, material, and labor). My math says it takes 21yd of concrete for a 4” slab. At $160/yd that’s about $3400 for the material. So over $8k in labor for a slab seems ridiculous. Is it really that hard? Anyone do this themselves?
I'm curious on by yourself? Just me, and I've done concrete. That's a slab that takes several guys to tend and I'd go more than 4" for a pole barn, do you have a Bull float?
And poles to go with it? Or any hand floats, an edger, how are the trucks getting to the pad? 1 truck is 9 yards. This half of the things to know just before you pour, you have to form it rebar inside the pad after its fomed. When it does get poured, it needs to be screeded flat for that slab I'd have min 4 guys 3 great guys that know what they are doing, you have roughly 90 min and then it starts to harden. All hell breaks loose just moments and during the pour and till finished. It's a orchestrated whoop *** cause it has a time limit. But ya you could do it.