The air cleaner that we use here at TKB Trading, LLC is the Friedrich C-90B Electrostatic Air Cleaner, which runs about $450 - $500.
This is an expensive air cleaner for "consumer level" (as opposed to even more spendy "industrial level") products. It is also somewhat bulky and not particularly attractive. But we really like it because it seems to be quite effective at keeping the air in our studio fresh, it doesn't have a huge energy demand, and it is easy to clean.
The fact that there are no filters to purchase and constantly replace was a big seller for us because we generate a lot of dust. You simply remove two pull-out filters and rinse them down with water before replacing them. We wash ours about once a week and always "ooh and ahh" over the amount of particulants that we send down the drain instead of breathe into our lungs.
Also, the unit received a #1 ranking by Consumer Reports (when compared to other consumer level machines).
The machine only really works in about 500 square feet of space, so we actually have a couple of them. We don't run them during the day, because they would be noisy and also they blow fresh air which can actually kick up more dust in our powder studio. Instead, we switch them on every night and let them do their duty while we sleep.
For more information, type the product name into a search box and browse the net. As of this posting, www.sylvane.com was offering the unit with free shipping at $489 each. At that site, there is a lot more detailed information about the product.
Hope this Helps!
For more information about our company and products, visit www.tkbtrading.com or www.wholesalecolors.com.