Product addons are the extras that can be included to the product at the time of the booking. To add these addons, go to Emprise Theme Addons > Product Addons and enter the name of the add on.
And when you create a product, you can select one of these addons. Also, you will be setting the price of these addons in the product itself because we believe most of these addons price will vary depending on the product and its location etc.