In addition to displaying Contracts via POS buttons, you can configure your POS to display a New Contract button in the POS screen. This button, shown below, is OPTIONAL.
IMPORTANT: If this button is used to sell a contract associated with documents you want your customers to sign, they will not be prompted to sign.
If you want a contract to be completed by the customer before taking payment at POS (like with a membership agreement), configure the plan on a kiosk storefront. See here for more information.
Add/Remove the New Contract button at POS
Go to Manage > Organization & Facility Settings > Facility: menu > Point of Sale > Options
Click Edit, at the bottom of the screen, then check the box to show, uncheck to remove.