Build the options your products need — engraving, embroidery, gift wrap, print-on-demand — with an amount on each choice. Gorvina shows you, order by order, which paid options were never charged. The amount is added to the customer's invoice — they settle it or they do not. An order carrying several surcharges is billed from your Shopify admin, one line at a time. Five field types, per-product rules and a preview. No file upload yet — we say so before you install.

• Five field types: list, checkboxes, color swatches, short text, long message
• Per-product rules — engraving on your bracelets, not on your shoes
• Bill back a missed surcharge — Shopify invoices the customer.
• See the surcharge applied on your own checkout, in one click
• Preview your fields, product by product, before you publish them