Very interesting topic and I heve the Popcorn and the Coke standing ready
Now, I am not a pro photographer and I do not live from selling photos but so far I have sold about 500 framed photos in exhibitions as well as 2 photos for brochure and Company logo.
Averything went fine except with a German Agency which bought the photo for a brochure for a digital camera producer back in 2008
They saw somewhere my image and asked me how much for it. I asked waht di you want to use it for ? They told me that want to include it in a brochure for a digital camera and the printing would be sized A4 adn they gave me the quantity of the printing and I gave them a price.
OK a few weeks later they send me the brochure and for my surprise my image was printed in Double A4 size (first cheating from the agency). Maybe 2-3 weeks later they asked if they could again use my image for the presentation of the digital camera as Posters and flyers and decorating stands and I told them NO because you were not honest and it would cost them again. Never ever heard from them again. SO >I do not even know if they just ignored me and used it anyway.
The world is getting lest respectful day by day
Here under this link
http://tinyurl.com/nryee7o you can see on page 2 and 3 the image I sold to the german agency
Just as a note aside about the way of thinking of some people ...