This is what I did: I asked what my clients budget was. I know that a 30 sec professional commercial animation can go for anywhere between $150,000 to $1,000,000 ... but who but a huge company can pay those rates? I say "be flexible." What I ended up charging was about $1200 for every 10 sec segment. This was for the Earth X short film for Marvel Comics/Alex Ross. Marvel didn't put up a penny. Alex paid out of his pocket. That's what he could afford. I don't believe there is an average rate. It's what you can get and what they can afford and if you want to do it or not depending upon the amount of time you put into it. Remember 720x486 is broadcast pixels when you render this out.