cleaning it - from $8 to $10 for a package that can be used several times
replacing it - $45+ for the filter
you should clean it every 6 months or when it's dirty... in SoCal that means about every 4 months
in daytona beach it probably means sooner.
annual precipitation in daytona beach area, florida: 50-60 inches per year
annual precipitation in l.a. area, california: 10-20 inches per year
anyway, i'm bored