Collectible Folding

Can old, collectible paper currency that has been folded and creased be straightened to make look new again?

It is not wise to do so, for then it will be considered doctored. This can reduce it’s value and depending on the note by quite a bit. You can also cause more damage by trying to so-call fix it.

My Top 7 Collectible Tactical Folders (Plus Affordable Display Stand)