It depends on you how you value your work, and what you feel customers want to pay. For physical products, we generally recommend royalties between 10% and 15% with an average around 12%. The standard prices for most Zazzle products are set so that with royalties up to 15%, the prices will still be within what customers expect to pay. At the higher royalty rates, the retail comparable would be for high-end art and designs.
For Instant Downloads, we recommend setting a royalty rate within 5% of the rates as defined below. For example: Holiday Cards can have a range of 87% to 97%.