Hi there! I have spent about half of my professional life editing product images in Photoshop, so this is right up my alley =) I can send you links to websites, Amazon pages, eBay accounts, Etsy shops, etc with thousands and thousands of product images I have done; both with editing photographed products and even creating digital renderings of products to make them look like real photography.
My schedule is flexible and open, so ongoing weekly projects would be a piece of cake. I am available by phone, text, Skype, Google Hangout, etc. Like you said, I am also open to however we want to structure the compensation; if the images are very similar with similar changes then the cost would be lower than completely different images with completely different edits. Also, the level of detail in the image is a factor; for example, cropping out the background behind a product in a square box is exponentially easier than cropping out the background behind someone with big, frizzy hair!
So anyway, my $250 bid obviously don't have any substance to it without knowing exactly what the project entails and how many images we are talking about, but either way, I am interested so let me know... ;)