Changes the federal definition of “manufactured home” to include homes built with or without a permanent chassis. Requires each State to certify that its laws and regulations treat homes without a permanent chassis the same as chassis-built manufactured homes, sets certification deadlines, creates penalties for noncompliance, directs HUD to coordinate with other Federal agencies, and requires HUD to provide model guidance to States. It also clarifies that existing Federal preemption of certain State laws remains unchanged.