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The Marketplace for Voice Talent
Resources > Agreeing Upon Terms
Once you have found your narrator, settle upon the final price and deadline for completing the recording. It is also recommended that you have the narrator agree to a full-buyout which means that you wholly own the rights to the recording and do not need to pay the narrator any royalties derived from future sales.
Royalties for Narrators
This is very specific to the individual narrator's experience and visibility within the audiobook industry and popular culture. You can contact the The American Federation of Television and Radio Artists (AFTRA) or the Actors' Equity Association for more information on representation and literary agents as well as industry payment standards.