If it's a union contract/agency, then it will be pretty straight forward. That said, even if it is a union contract, you can make an appointment at SAG or AFTRA and they will go over the contract with you. If it isn't union, I'd recommend hiring a lawyer to go over the contract. Make sure it's for your area only, and doesn't prevent you from having representation outside your area. And make sure that their commission is always 10%, no more!!!!
Better yet, ask if they will do a verbal agreement. I'm at a rather large agency in LA, and I don't have a signed contract. When I was at William Morris I didn't have a signed contract. Most of their
VO clients didn't.
One HUGE piece of advice for everyone regarding agents:
If you do sign a contract,
don't sign for more than one year...ever!!!!!!!!!!!!! Your ego will be boosted when they ask you to sign for 3 years. "Wow, they must really love me!!" But that just gives them the power and you no leverage. They may fight you on this. But there are very few times we have any control in our careers. Don't give anyone more of your life contractually than you need to. If all is well, you can re-sign after each year.