The way I see it, editing needs to be at your convenience; I'm one that works on deadline and if you're working on deadline I can help.
Rate Per Page
Rate Per Word
Rate Per Hour
NOTE: these rates are not set in stone and are only an average for this editor. The actual rate applicable to your document will depend on the depth of the edit, the quality of the writing, the topic matter, the proximity of the deadline, the length of the document and several other factors.