(a) Nothing in this subtitle shall be construed to prevent the owner of real property used by the public for purposes of vehicular travel, by permission of the owner and not as matter of right, from prohibiting such use, or from requiring other or different or additional conditions than those specified in this subtitle, or otherwise regulating such use as may seem best to such owner.
(b) Nothing in this subtitle shall be construed to prevent the owner of a private roadway in a planned community, having granted express permission for the state and local law enforcement authorities to enter on and to enforce the state and local traffic laws, from revoking the permission and notifying the state and local authorities of the revocation of the permission.