Ask HN: How do freelance developers determine the scope of projects?

We're working on a new startup that would connect freelance developers with qualified projects.<p>The question is, what criteria do you use to determine the scope of a project? A response here or in this quick survey would be highly appreciated!<p>Survey: https://docs.google.com/spreadsheet/viewform?pli=1&formkey=dFI4cjQxQmRFR3FoUlNZRzVVRkJWeUE6MQ#gid=0