skimmed through this thread but thought worth making a couple of points -
For proof of ownership, as has been said, shoot RAWs but isn't that a no brainer anyway?
Re. permission of the subject in the pic - need to distinguish between editorial use and advertising. If I'm in a public place and photograph a member of the public/surfer going about there business, as long as they're not a minor, I can sell that image whether the person is identifiable or not, for editorial use (print or web) as long as nothing defamatory is implied in the caption or article about them. If a corporation/shop wants to use the images for advertising, branding etc a model release is required, and a property release as well if on private land (is there any private sea?!?). Ultimately the onus is on the photographer to ensure this is in place and stock libraries insist on a release if the image is to be sold as model released. Use of an image for advertising/marketing branding should command MUCH heftier fees. Yes there are millions of royalty free images out there but the higher price in part is for exclusivity, assuming the images is not royalty free but rights managed instead. Don't sell your images short.
And the easiest and quickest way to price an image, to get you in the ball park (and i know of professional photog's who've used this method in court when claiming damages for unauthorised use) is go to a stock library and price the equivalent. www.alamy.com
not top end but a good starting point.
Hope that helps, rather than muddying the waters further.