Paperwork. No one seems to like it. But a proper paper trail, besides demonstrating to clients that you are a professional, can save your business and more when things go wrong - if you do your paperwork right.
Several software packages have been designed to generate such forms, and most professional accounting packages can be adapted to generate customized estimates, invoices and more. All should include license and terms appropriate for the project. And all are essentially contracts, so be sure to review them with your attorney before offering or signing them.
Photographs are under copyright protection the moment they are created and fixed in a tangible form. The copyright laws in the United States give authors certain exclusive rights to their original works for a limited time.
A primer for photojournalists on copyright and rights
U.S. Constitution Article 1, Section 8, Clause 8
The Congress shall have power ... to promote the progress of science and useful arts, by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries....
Stock, or existing, photography is valuable to editors and art buyers, because it is a known quantity - and quality - available immediately. An image from a student photojournalist is worth the same as an image that is equally good (and/or appropriate for the use) as an image by a seasoned pro, since the quality can be seen and judged immediately - even though the assignment rates for the two might differ widely.
Before you can price a product or service, you need to know your costs to provide it. This calculator is one tool to help you get a handle on those costs. It lists annual expenses independent photojournalists need to account for. But it's only as accurate as your inputs, which can be hard to estimate. Err on the high side, since unexpected things can catch up with you, and as you bill more, your expenses almost surely will increase. As high as totals from this calculator may look, experience will probably prove them low.