They usually charge for a fee which may be as low as $15 or as high as $250. Often, they guarantee a specific number of jobs when you sign with them, but at the current rate of $30 per day for such non-union work it is unlikely that the amount you earn will equal the advance paid. Be sure you understand what their contracts promise before you sign, don't rush. If anyone pressures you to make a quick k decision that involves your money, think twice and use caution, as few of these companies have a tendency to disappear overnight and reopen under a new name. The SEG can send you a list of casting services that they recognize and who will help you with getting into the union if you are registered with them.