What advice would you give to authors who are considering turning their book into an audiobook?

An audiobook is a fantastic addition to a growing backlog of your books that are already selling. Books in the midlist and above can definitely benefit from the added exposure and price differential that an audiobook can provide. However, an audiobook is not going to sell magically for an underperforming book. Before pursuing an audiobook addition to your catalogue, be sure your books in print are as good as they can possibly be. The audiobook is the cherry on the cupcake.