I have been called on this in the past but I can't see $500.00 for a filter
system and maybe $50.00 a year in cost maintain when a good 3M will do just
about 99% as good as a Aprilaire system. For that 1% better the cost is high.

Your Call and not mine.
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I agree with Turtle.

You're best off buying Filtrete Ultra Allergen filters in bulk from
one of the many online E-tailers and changing it 4 times a year.

Plus, if you enter a particularly 'stinky' period, like doing alot of
grilling in the house, you can easily change the filter without
thinking about cost.