Air purifiers and air monitors. It is shocking and disgusting how much dust and particles these air purifiers suck out of the air. The air monitors detect when to open windows for CO2, among other things.

My allergies no longer exist.

Edit: A few people have asked for recommendations. I recommend the Coway Airmega AP-1512HH for larger spaces and Blueair Blue Pure 411 for smaller spaces. For the air monitor I have the Qingping.

Hm, I'm looking to eradicate smells from my house. Do air purifiers help getting rid of that old-house smell?

Yes, if they have a charcoal filter. The Coway AP-1512 is a favorite to handle both odor and lower particulates.

I have three.

There are a number of past threads where people discuss their enthusiasm for this model. Have a search.

Can second that - I have four of them, they run 24/7 on medium and pull ~8 watts at the wall each, assuming my meter is accurate. Picked them up after the last big discussion on air quality here a few months back. They are the Wirecutter pick, I believe.

I keep an agent that monitors amazon pricing on the filters, and just buy a bunch when they dip abnormally low. Have you found any other ways to minimize cost on them? I have only used the ones sold by coway, as my pal tried some 3rd party and they were jenky.

Depending on where you live, filters are a once/twice a year expense, I believe (I’m only a few months in). Honestly my advice would be: just be diligent about maintaining them. I vacuum out the filter and charcoal screen once every couple of weeks. Takes a few minutes, pretty painless. Amazing how much dust they pick up in normal operation.

Incidentally, which agent are you using for Amazon?

I've considered setting up Huginn to do this, but haven't explored it enough: https://github.com/huginn/huginn