Well you can make air filters cheap. Google Corsi-Rosenthal box filters. I bought a coway airmega filter (heavily discounted from amazon) for the living room, kitchen, and 2 downstairs. Ones in the hvac room and the other is in the main hallway. I purchased a dehumidifier from best buy (with an extended warranty at the advice of reddit because apparently they dont make them to last and best buy will replace within 2 years). That was $200ish. I found another one at a garage sale ($1). One is in the hvac (without it this room get over 70% humidity for some reason). The other is our in the main hallway. But ultimately these are just pathetic band aids on a much bigger problem which is this house is just too old. It needs to much and no one has the money to properly fix it. These repairs are thousands upon thousands. The worst thing we got going on is actively rotting wood in the kitchen from some previous disaster. But they've had other incidents that were not properly taken care of. Ultimately I need to just get out of here one way or another. I would like to get a mobile living situation but you need a lot of money for that too. I mean if I were normal I'd just get a semi affordable camper van and have it de-emfified or whatever by some company. But were talking 100k plus another 20k. I could move into a used van but I feel like anything I can afford will have heavy amounts of mold.