The condition & rarity of a banknote are the most important factors when determining its value. A collectable note that is in uncirculated condition, will be more sought after than one that has been circulated, soiled, folded or torn. Rare banknotes can be extremely valuable even if they are in poor condition.
The serial number , signatory , historical significance are some of the other factors that contribute to the value.
Two notes may have the same signatory, but if one has a collectable serial number, such as a replacement note, it will have a higher value. Replacement notes are notes that replaced damaged notes in the printing process. The serial number of South African replacement notes start with the letters W,X,Y or Z.
Misprinted and error notes are also collectable.