In notaphily (paper money collecting), the condition of the note is crucial but the serial number can multiply its value significantly. Fancy serial numbers are highly prized.
Types of Fancy Serial Numbers
Solid numbers have every digit the same such as 111111 or 999999 and are extremely rare. Radars read the same forwards and backwards. Repeaters have a block of digits that repeats such as 123123. Low numbers start with many zeros, and the lower the number the higher the premium. Ladders have digits in perfect ascending or descending sequence such as 123456.
Where to Find Them
Finding fancy serials in circulation is like finding a needle in a haystack, which is exactly why they are valuable. Always check the serial numbers of crisp new notes before spending them.