Current factory cards do not add significant value to Hagen-Renakers. Most collectors remove new Miniatures from cards.
Older cards (pre-1990s) and stickers are interesting artifacts and part of Hagen-Renaker history, so I do not recommend removing them, but again, they rarely justify an increased price for a Miniature. Cards and stickers can, however, add value to Designer’s Workshop, Pedigree Dog, Disney, and other lines.