Ladders, with or without jacks, straps, stabilizers or other supports.
You have that 18-24" in front, above and below you. Nothing to either side or behind. No place to set something down short of a bag or two on a chain or rope. Not easy to look though that to find a small tool. No place to step if you legs get tired and the rungs can be a bear on the knees.
Scaffolding.
You have room to move, crouch, kneel, sit or lean to the side. You also have room to set tools, parts and fasteners down and arrange them so you can see to make selections as needed. You can take a step or two, maybe three, but not too many.
I think you're supposed to be able to climb up the ends and step onto the platform, but I never do that. I can't climb straight up. I set a ladder next to it at a comfortable angle and strap it to the scaffold.
Several have and it's been answered. Check the post directly above yours.