They are already being used for building inspection and site inspection.
And outfitted with thermal and infrared cameras for crop inspection of small sites.
I was on a “webinar” that showed the ideal of having a swarm of drones go through a large building under construction each evening with the results ready that morning showing the “as-built” compared to the plans. “Knowing that beam is off by 3 inches now rather than a month from now will save a lot of money.”
Using drones with remote sensing tools, such as tiny magnetometers, are in use now scanning sites for buried metal - especially in possible dangerous areas such as unexploded ordnance at old test ranges.
Speaking of drone swarms - the last Super Bowl light show had 500 drones acting in concert.
Not the superbowl - but a good video on the first time 500 was done.
https://www.youtube.com/watch?v=aOd4-T_p5fA