You do need a commercial rating to do Photo work if you charge for it. My insurance did not go up for doing it. Mainly pictures of Ranches for the Real Estate world. Now you might break even on the total cost of doing this but it is not in big demand at least around here. Ask yourself how much would I pay for a picture of my house from the air? Like Ed I have done more for free or as a favor to friends. I also fly Hunters to look over their leases from the air , cost of gas plus. Not much in the way of tax relief since it becomes such a small percentage of total cost, meaning you can't write off the whole expense for the year.