Addendum
Extra product fields with prices, and a customer artwork upload - checked by what the file really is, kept private.
Addendum is for WooCommerce print, engraving and custom-order shops.


Inside Addendum
Fields in a few lines
text, text boxes, dropdowns, radio choices, checkboxes, quantities and a file upload, written as a short list on the product - or once for whole categories.
Prices your way
per item, once per order line, or a percentage of the product's price; each choice can have its own price.
Checked properly
required fields, character limits, ranges - on the server, with the mistake shown against its field.
Uploads you can trust
a file is judged by what it really is, not its name, size-checked, and kept private under a random name. You open it from the order.
Prices worked out again at checkout , never taken from the browser.
Tidy
uploads never ordered are cleared after three days; ordered ones are kept.
Before you start
Asked first
What kinds of file can customers upload?
You choose per field: PNG, JPG, GIF, WEBP, PDF, SVG, AI, EPS or TXT, with a size limit.
Where are uploads kept?
In a private folder under your uploads, closed to the web. On Nginx hosts, make sure that folder is denied too.
More for the storefront

Admittance
Sell event tickets as WooCommerce products, email a named ticket with a QR code per seat, and check people in at the door from a phone.

Chit
One store-credit balance per customer - no codes. Refund as credit, give credit with a reason, spend it at checkout.

Cogwheel
WooCommerce cost of goods and true profit, with payment fees and labels