Why is this so expensive? It's literally 4 PC fans and some plastic trays? I presume you bring your own filters.
If you were actually looking for an answer, the AirFanta's creator Adam Wong recently answered a question about this:
Production costs include raw material procurement (my fan and filter suppliers are happy, since each machine requires four fans and four filters—more than they supply to other brands) and labor assembly costs. In addition, there are shipping costs from China to the US, Europe, and other regions, warehousing fees, and last-mile delivery fees. For what it's worth, in the US, shipping this 17 lb box already costs about $18. Also, Shopify and credit card channels take just under 5%. We also hope to promote on Amazon in the future. Estimated advertising costs are 20%, and Amazon charges another 15% in fees, so that adds up to 35%. If you're not in this business, it's normal not to know these expenses. But I have to say, the costs are much higher than they appear on the surface.
120mm high static pressure fans are £7 (so £28), an AC power-supply fan controller £11. IKEA filters are £3 each, so £12. So we're looking about £50, be generous and chuck in another tenner for 3d printed ABS and screws etc. £60 all-in at 1x retail/Amazon prime prices, delivered to my house.
If I was doing this at scale I am sure I could get lower than the retail Amazon prime prices. But even if I couldn't this is about half of the £130 RRP. Yes there are labour costs to assemble this but this is not exactly a swiss watch and looks like it comes flat packed anyway?
Do note that the AirFanta uses 140 mm fans, and IKEA filters are E12 vs E11 so the airflow would be less optimal[1], but hey who's counting. ;) Also I envy how cheap your IKEA filters are; in the US they're $18 & $25 now.
[0] https://cleanaircrew.org/box-fan-filters/
[1] https://twitter.com/Engineer_Wong/status/1899144721710408038
https://makerworld.com/en/models/2470181-nukit-tempest-euro-...