To avoid them stealing your work: One thing I do is not read the entire script, or make a few changes (like names or phone numbers.) I don't watermark because they're distracting. In fact, when I receive watermarked auditions, I delete them.
Payment Policies:
If your agent books the job, agent collects for your and pays you after taking his or her cut.
If client is international, I ALWAYS require payment in advance by credit card--no exceptions.
If client is in USA, I encourage payment in advance by VISA, Mastercard, Paypal, or Voices.com's SurePay. I encourage it by bidding one rate for PIA and a much higher rate for check immediately upon delivery.
I do allow some clients, for whom I've worked for years, to pay by check. It should be noted, that most of them have money in my mailbox within a week.
With these terms, I usually get paid quicker than most talent. If a client is slow pay, I won't work for him again. As a one-person office, I don't have time to waste trying to collect on
VO jobs!
You will be stiffed on occasion. Note, the low budget clients tend to be the ones who take forever to pay! One client who hires for commercials online and says he'll "use you a lot" only offers $75 per spot and takes months to pay. But for someone like you who hasn't done any work yet, it may be worth it.