I like to get as much information as I can about the project ahead of time:

• What's the scope of work
• How long is the project
• Do I find the project/material interesting
• How well have they planned for audio post (or haven't they)? What do they want the audio to do in their project?
• Do I have the time to provide what they're looking for?

I've mentioned in another thread on this site that a project can described as "Good," "Fast," or "Cheap." It can be any two of those three ideas, but it will be the direct opposite of the third (i.e. for a project to be "Good" and "Fast," it will NOT be cheap..."Fast" and "Cheap" will not be "Good"). This is one of the biggest factors for me to be involved in a project. Personally, for freelance work, I will not allow myself to work on something that will not be good. [I have less say at my day job. ;)] My work reflects on me and my skills. If the circumstances do not offer me the opportunity to put forth my best effort, I will not take it. Which brings me to the next idea.

Do not oversell yourself...to the client, or yourself. If you have doubts about your ability to handle a particular assignment, make sure you evaluate them carefully. Know what you're getting yourself into. Know what your time is worth, and what the different tasks for a project requires. Completing any project is a system of controlled attrition; you won't be able to do everything perfectly. Make sure priorities are discussed and agreed upon (this goes back to the "scope" bullet-point), before you agree to start on the project.

And don't forget, you don't have to be the only audio person who works on a given project.

Hopefully the picture isn't shot yet and they're taking you on in Pre-Production.

Ask for information on the project. Is it a paid job? If so, do you have the time to work for free or not? If it is without pay, I would definetely ask to see the film in advance - if available. If it isn't shot yet, I would like to read a synopsis or treatment. If I know the director in advance, either in real life or by reputation, I could also make my decision based on that. If for instance I was asked to work on a film by David Fincher or Lars von Trier, I would probably say yes at once. If my schedule was free and the job is paid I would also say yes.