Possible product example. Let's call it the D&D Treasure Hunters System, for lack of anything better right now:
Illusionist class, Book A -- quality softbound, 5x8" (or so), color illustrations, packaged with one of three miniatures (wizards, of course!) and two additional "secret bonus" miniatures (a random familiar, for example, or attachable mage staff). ... The book provides a full class progression for this specialist wizard track, including five new spells and feats available only to an illusionist, and statistics for the illusionist's familiar. Three pages of full-color art in the back suggest possible traits to help you envision your unique character. An introductory story chapter provides a detail-packed background of the standard Illusionist's early training. (This product requires Basic Book of Arcane Spells, available separately or with the D&D Treasure Hunters System.)
Illusionist class, Book B -- as above, plus three higher-level spells, a five-level Prestige Class option, and a familiar miniature unavailable anywhere else. "Rare" production run!
(Next month: Illusionist class, Book B, SPECIAL TITANIUM COVER and 'WILD' SURGE DIE - '2' face is actually an extra '19' instead! ... Fully compatable with D&D Treasure Hunters System)
Lest ye nitpickers get tangled up on the specifics, let me state clearly: IT'S JUST AN EXAMPLE. A potential mock-up. I'm sure the pros could come up with something more appropriate and sales-worthy.
Anyway. ... You wouldn't have to foil-wrap the entire book to make it collectable/valuable - just look at toy action figures or Beanie Babies when they were being grabbed directly out of the shipping boxes at store doors.