Treat the card as art first
A sketch card may come from a trading-card product, but the front is an original work. Two sketches by the same artist and subject can have dramatically different composition, detail, and collector appeal.
That makes price comparison less mechanical than with standard parallels.
Record the artist
Artist identity is one of the most important fields. Preserve the artist name exactly as listed by the product or confirmed through signature and reference material.
If attribution is uncertain, record it as uncertain rather than guessing.
Evaluate the image
Consider likeness, composition, background detail, color use, medium, orientation, and how strongly the piece reads as the intended character or scene.
Personal taste matters more here than in most checklist-driven collecting.
Understand foil or stock categories
Some products group sketches by card-stock or foil treatments. That category describes the official format, but the artwork itself remains unique.
Do not treat a sketch checklist slot as if it means several copies of the same drawing exist.
Protect provenance
Keep purchase records, artist information, product identification, and clear scans. For a one-of-one artwork, provenance is part of the collectible's history and can matter when the card changes hands.
Connected archive