Photoshop Backdrop Extensions and Fix Shadows in Photos

I have roughly 25 team photos and maybe 100 individual photos that need some touch up work done. They need the backdrops extended and the shadows around the people cleaned up a bit. Let me know if you plan to just extend the backdrops and clone-stamp around the people to remove the shadows or if you plan to do that and cut out the people similar to a green screen type deal. You can determine if you want to do a price per image since I am not 100% sure of the exact number or if you want to bid to do the whole job up to a certain amount of images. I can say for sure that it is over 20 of the team photos but not more than 35 and at least 50 individual photos similar to the ones I have attached but most likely closer to 100. The images I have attached are some of the more difficult ones. Some are going to be way easier than these, but just to be on the safe side you can bid based upon this level of difficulty. See the attached photos for examples of the work. I would post them in a Dropbox folder for you to download. I would need these done in a couple of days. No later than Sunday night.