A concrete pump truck. If you're in an area of new construction.
This is separate from the concrete delivery truck coming from the batch plant, your job is to move the material from the back of that truck to where it's needed on the jobsite using the strong pumps on your truck, and the lifting arms which act like a crane and position the flexible hose right where the operator wants it to fill the forms. In the old days it was lots of guys and wheelbarrows. You co-ordinate with the concrete contractor, who co-ordinates with the delivery driver. You show up and get ready, the delivery truck shows up, you pump everything they want pumped, you clean your equipment out at the jobsite with their water, and you're done.
The truck is going to cost quite a bit, but that's really all you need. That, and a place to park it.
In my area there is only one, and he's popular.
Some knowledge and experience with concrete would be beneficial, but the concrete guys will teach you, for better or worse, most of what you need to know, mainly by swearing at you.