Need automatic authenticity certificate generation for handmade items

I run a small handmade goods business (jewelry, ceramics, and textile art) and want to add an automatic authenticity certificate system to my website. Right now I write out certificates by hand for every piece, which is slow and does not scale as my catalog grows, and it is easy to accidentally reuse a number.

I need a developer who can build a feature that generates a unique certificate automatically the moment an order is placed or a piece is marked as sold. Each certificate should carry a unique serial number, the item title, a short description (materials, technique, creation date), and space for my signature or a stamp image. The system also needs a public verification page where a buyer can enter the certificate number and instantly see that it matches a genuine registered piece from my studio. This matters for people buying pieces as gifts or as collectible investments, and it also protects my brand from imitators.

I would like the certificate to be downloadable as a PDF and printable from the order confirmation screen. Numbering should never repeat and ideally should follow a readable pattern, such as year plus sequence. I am open to suggestions on templates as long as the result looks professional.

What I need:
— Automatic certificate generation triggered on order or checkout
— Unique, non-repeating serial numbers
— Public lookup page to verify a certificate by number
— PDF export and a print-friendly layout
— Simple admin panel to review or reissue certificates