There is nothing that affects more the listener experience than having mistakes on your audio production. The most common issues are repeated sentences, followed by missing fragments; but I have even seen cases with outtakes and swearing included in the final product. This is a shame and could be easily avoided with audio proofing. If you follow my reviews, I always leave comments when this happens, and include details about when it happened. I understand audio proofing can be a tedious task after you finished recording but it is a necessary step in order to deliver high quality audiobook.
The fee $25 per finished hour, including an annotated script with errors highlighted directly in the manuscript and accompanying error code notation. I can also verify whether it will meet ACX standards.
Please contact me if you want me to audio proof your audiobook.