Extended warranty

Hi
what's the best way to include the option to purchase an extension of the given warranty at a price that is a percentage of the total products price?
Thanks

Hello,

There are several way to proceed but we think that the most simple way is to add to your product an option.
In your product backend an option is another product, that can be added (with his own price) :


Then, your customer will be able to add a product associated to this product, here your warranty, see this documentation .
Hope this will help you to achieve your needs.
Regards