Mapping is completely different from inspections and requires different flight patterns, software and usually far more batteries!
Additionally, you do not say what country you will be operating in as this will have a bearing on costs regarding training and certification.
Nailed it.
It's for visual inspections and mapping in OH power lines.
How long of a corridor? If you're doing 1/4 mile sections, not a big deal. But my work with power companies has involved very long corridors up to 14 miles long. I find the most efficient number of batteries to have is 10, which assumes you have an industrial-grade battery charger in your vehicle. There are two ways to go. I went the techy route and built my own. But my partner went the converter route and had a car stereo place install a high amperage charger that's wired directly to the car's battery. I think he spent about $2K all tolled.
I considered all those factors in the initial investment, but a flight is a flight, doesn't matter if it's above a bridge or a building - or so I thought.
If you're shooting video and delivering a finished product which might include titles, graphics (like arrows pointing to issues, etc.), digital zooming, etc., then you're going to need a video work station and software. I use Adobe Premiere Pro, which costs me about $30/month for the entire suite. This is a discounted price for educators. I think it's like $50/month without the discount.
You will also need to invest in an editing machine, which is essentially like a gaming machine. My editor is a dual Xeon monster with 132GB of ECC RAM and a GeForce GTX 1080 Ti GPU.
To my understanding, operational costs are the least of the problems in UAV flights as it comes mostly from the equipment itself and its maintenance. Maybe software processing too?
Yes, no, yes.
Obviously you have your initial investment in your UAV's, cases, etc.
Provided you don't crash, maintenance costs are nil. The "cost," if you, will is your time and diligence, which mostly involves good battery maintenance and storage.
If you're mapping, that's a whole other ball game and investment package. How far you wanna go down the rabbit hole? There's a HUGE difference between simple orthophotos vs actual architectural-grade "maps" (which is what we do). The latter requires a ton more work, a larger initial investment and greater operational costs. And, as I already pointed out, if you're presenting videos to clients, you will DEFINITELY need an editing station.
Good luck.
D