I’ve heard good things about the DJI Mavic 3T, especially for powerline inspections. Its thermal and zoom features seem really useful. Just getting too close to the powerlines can mess with the signal, so keeping about 30 feet away is usually a safe bet.
If you’re thinking about offering powerline inspection services, you might want to take a look at this high-voltage contractor in Ottawa:
https://kanatautilitiesltd.ca/high-voltage-contractor-ottawa/. It might give you some helpful info or even lead to some good connections.