For safety, aircraft can’t fly below certain altitudes as regulated by the FAA. This is not necessarily a limitation for photography. Sometimes the preferred perspective is the broad aerial landscape scene showing context. But when details of a structure or a property need to be revealed, the distance from a manned aircraft may be too great.
When a ladder or cherry picker is too low, and manned aircraft is too high, a tethered helium balloon fills the gap in altitude from 50′ to 500′. I use a setup from Southern Balloon Works.
The balloon is tethered with two lines. The camera is attached to the blimp and supported on a custom housing which is radio-controlled via a ground station. The ground station includes a monitor so you can preview the image. It also has controls for pan, tilt, zoom and shutter release. The camera housing has a set of gears that enable zooming of the lens remotely. The housing itself allows control of pan and tilt.
Here are two photos of the same property, taken from two different altitudes, with the helium blimp.