Display | Custom Fields | Item | Main Attributes

Hi,

1. It's to add HTML attributes to the field. For example, you could write :
autocomplete="off"
and that would disable the browser autocomplete on the text field.

2. Two ways are possible:
- options allow you to add such fee, so you could use an option instead of a custom field for the fee. However, there is no setting to link the display of a custom field to an option. So you would have to add some custom javascript on the page to handle that yourself. It should be a matter of a few lines of basic javascript so any developer should be able to do that.
- You could keep using custom fields, and have a price override plugin developed to change the product price in the cart based on the value of the custom fields (basing yourself on the donation plugin in HikaShop). It should also only require a few lines of PHP code.