This field is a standard field that allows the seller to choose the payment types they accept as payment for a specific listing.
Highlights of this feature:
You determine the choices allowed for sellers to choose from site wide within the following admin tool:
LISTING SETUP > PAYMENT TYPES
The following is a screenshot and further explanation of that admin tool:
All the choices you see in the above admin tool would be the options that all users who see that field will be able to choose from. There are only site wide choices but you can control site wide or by category where that field will appear if you like.
You can determine if this field is an option for a seller when placing a listing site wide here in the admin tool:
LISTING SETUP > FIELDS TO USE
The following screenshots shows where you would enable, make it required or editable:
You can determine whether to allow this field on a category by category basis within the category specific field configuration admin tool found here:
CATEGORIES > CATEGORY SETUP > [EDIT NEXT TO CATEGORY TO AFFECT] > [FIELDS]
You see the same type of admin tool that you see in the LISTING SETUP > FIELDS TO USE admin tool to change on a category by category level.