A grading contractor levels the pad — the dirt work that turns a spot on the lot into a place a home can sit level, drain away from itself, and be reached by the truck.
Short answer: The grading contractor clears and strips the spot, cuts and fills to a level pad slightly larger than the home, compacts it so the piers do not settle, and shapes the ground so water runs away from the home in every direction — the state installation standard calls for positive drainage for the first ten feet. The same contractor usually digs the footers, cuts the driveway and sets a culvert if the drive crosses a ditch. A pad that drains is the cheapest insurance against a home that will not stay level.
Reviewed by a manufactured home setup contractor and dealer.