It wasn't super cheap, but in relation to the cost of a vast collection of watch bands it was cheap enough (to me). Also, the 1/1 ratio of €/$/magnet doesn't hold when you buy a larger amount. I got 72 magnets for 48 Euros 48/72 and the IKEA white boards were also pretty cheap. But yeah, it's more expensive than just throwing the lot in a big drawer.Simple, yes. Cheap, not so much.
The neodymium push pin magnets are almost $1/each (20 for $18 plus tax) on Amazon ... you need two magnets for each band... so that's 264 magnets for your 132 bands... at $18/20 pieces, it's almost $240 for magnets plus the cost of the white boards... there are other magnets that are cheaper (60 for $16 plus tax), but they are not the neodymium magnets, and may not hold as strongly - slipping, sliding down the board.
Do you have a cheaper source for the neodymium push pin magnets?