As both a writer and an editor I work using the rates presented by the Editorial Freelancer’s Association (EFA) as the starting point for negotiation. Do feel free to negotiate: the nature and difficulty of an assignment does affect the final settled price. The stated rates of the EFA, however, offer a reasonable and recognized set of prices determined by a non-interested party: this allows you the comfort of knowing I’m not just fantasizing a nice pay-rate and it allows me the comfort of knowing my rates are based on industry standards considered fair and reasonable by others in my trade.
My usual method is to negotiate by email, using the terms set in our correspondence to establish an informal contract understood and agreed to by both sides. In some instances I go further, and use an actual contract prior to finalizing an agreement.
I expect partial payment up front, with further payment scheduled to reflect the size and duration of the assignment. Under some circumstances I may request you commit to a kill-fee should you choose to terminate the agreement prior to completion, but this is something we would agree on in advance, prior to my beginning a project. Under ordinary circumstances I expect payment through Paypal. Alternate arrangements can be made, but Paypal is preferred: it’s simple and reliable.
My primary goal is to provide honest work for reasonable fees, with the maximum amount of transparency on both sides, so that both parties can enjoy confidence in each other and in the process.
Editorial Freelancer’s Association: http://www.the-efa.org/