Look at the route people and vehicles will use
S. 281 and State Highway 29. The area supports a mix of local events, residential properties, tourism-related activity, ranch and land work, and construction or maintenance projects. For temporary restroom planning, that mix makes the physical site more important than a city label alone.
A site behind a controlled gate in Burnet
The street address gets a driver to the property, not necessarily through the correct entrance. Explain visitor procedures and permitted vehicle times. Coordinate sensitive access details directly with the agreed contact rather than placing them in public directions.
Turn those details into a useful enquiry
Name the delivery gate and the role responsible for authorising access. Include the Burnet property address and the dates the facilities need to be usable. The listed city does not establish a local depot, a fixed delivery radius or availability at every address.