A drone makes snagging a roof, a gutter line or a tall elevation much faster and safer than a ladder. It finds the problems. What it does not do is make sure anyone fixes them.
Finding snags is the easy part
Anyone can write a snag list. The hard part is closing one. Items get marked done that were never checked, and the same defect turns up again on the next visit because nobody confirmed the fix.
Three states, not two
Open and closed is where snag lists go wrong. A useful list has three: open, fixed and verified. Fixed is the contractor saying it is done. Verified is someone checking that it really is.
Keep the before and after together
The photo that raised the snag and the photo that shows it resolved should sit side by side. Drone shots of the roof before the repair and after it make a far stronger record than a tick in a spreadsheet.
Report before you leave site
A list written up back at the office loses detail and arrives late. A report produced on site, while everyone is still there to agree it, gets acted on.
SiteInspect is an Android app that tracks every snag through open, fixed and verified, keeps each after photo tied to the before photo that prompted it, and prints a branded PDF while you are still on site.