HB 4150 expands the authority of the Texas Department of Transportation (TxDOT) to enforce county regulations concerning vendors and solicitors operating on public highways, roads, rights-of-way, and parking lots. The bill removes the population threshold that previously restricted this authority to counties with over 1.3 million residents, allowing all counties to regulate these activities. It also grants TxDOT the power to issue verbal warnings for violations, notify law enforcement, and remove non-compliant structures if they remain after 24 hours. If an owner's identity is known, they must be notified and given 10 days to reclaim the structure before it is disposed of. The legislation seeks to standardize enforcement and improve public safety by managing roadside commerce and solicitation.