just want to share my recent experience regarding cleaning banknotes. i did some research last night and the common advice that i found was either you hire a professional to do the cleaning for you or just leave your baknotes as they are - old, soiled, and crumpled.
being the guy with an OCD, i decided to throw this pretty reasonable advice out the window and washed my banknotes with soap and water just this morning. i figured banknotes are made of cotton so i guess it's just the same as washing my socks. it's not rocket science. i'll just be extra careful and everything will be fine.
well, things didn't actually turn out as expected. it appears, my english series notes are more paper than cloth, which didn't really go well with water and detergent. i just ruined my half-peso and 5 centavo notes in my failed attempt to improve the condition of my banknotes.
the upside is, i discovered that a simple eraser (the one that's smooth and white, not the usual mongol pencil eraser) gives a much better result than soap and water. soft and light strokes did all the magic.
so the lesson here is - if you're not really losing sleep over some minor stains on your notes, just leave them as they are. they're better off dirty than something which looks like a five year old's finger painting. take it from me, a two-month old stubborn and crazy banknote collector. lol! :D