|I've done a good few hundred hours in a Cherokee doing low level photography. Similar to being strapped to a ceiling fan, and you only get a break every 5 hours to put new batteries in!!
I was working for a operator who bulk photographed rural areas, predominantly dairy farms. He would then approach the people and sell enlargements on a door to door basis. I know financially it was quite lucrative, he enjoyed the sales pitch and travelling both by aircraft and car about the countryside.
You'd also have to have a good look into the CAR's at the legality and possible requirements for certification? There's quite a bit to consider, would you purchase or hire a aircraft? Are you the pilot? If so, who will photograph? (You'll have a good time trying to fly and take photo's) How would you sell the product? Mapping and correlating photographs to physical positions, etc, etc
Any Q's feel free to PM