A 20 yard roll-off needs about 22 feet of straight-line space and roughly 10 feet of overhead clearance for the driver to tilt the container off the truck. Bigger boxes need more. If your driveway is narrow or steep, tell the dispatcher — we'll match a size that fits and pick a driver who's comfortable with tight drops.
We put wood boards under the rollers by default to protect asphalt and concrete. Sealcoated driveways are the one thing to flag ahead of time — soft coatings can mark under the container weight.