(a) Except as provided by Subsection (b), the commissioners court of a county by order may erect and maintain motorist information panels in a right-of-way along a toll road in the county.
(b) The commissioners court may not erect a motorist information panel in an area that does not have a qualified business.
(c) The county must erect each panel on and below the exit identification sign preceding the exit direction sign at an interchange.
(d) The county may erect more than one panel for each interchange.