Maybe linking to a PDF of the sample chapters? Shopify can host those files, and then you can add a link to them in the product description or on a button somewhere on the product page.
To upload a file (instructions from Shopify docs):
Not a bad idea, except we are using an ERP integration to handle all of our product info, including descriptions. All product data is synced from our ERP to the website with some integration software. So unless the link for the PDF file is sitting in the ERP it won't work... and unfortunately we cannot have URLs in our ERP.
Any other suggestions?
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