We upgraded the carpet to vinyl flooring, did a bunch of treatments for the smoke (vinegar, ozone, Killz), repainted the cabinets, and installed some cheap upgrades throughout.

You can try the vinegar/baking soda fixes on the internet but only if you plan prop it open after fixing.

Spray bottle with 1/4 vinegar and water- light spray wipe all the walls and rinse with clean damp micro-fiber rags (ring out hard) rinse with plain water.

I don't know if gnats are a symptom of anything in the house except leaving the screens open or drains needing to be flushed (vinegar/ammonia).

I had a two week window to do it, so I didn't have time to get it tested for asbestos... so I just proceeded as if it had asbestos, got a P-100 respirator, face shield, tyvek suit...etc.The popcorn had a layer of paint over it so I had to spray it with a vinegar/water mixture.

But, the old saying goes that you attract flies with honey, not vinegar.

My process:Pulled all the flooring outSteam washed the walls, windows, cabinetsFollowed up with hand-washing using a vinegar mixPainted with an oil-based Kilz primerPaintedPut in new flooringIt's been two years and it still smells like fresh paint and carpet.

(Catch more flies with Honey than with Vinegar)Just my 2 cents.

Even putting a funnel and a bottle of white vinegar in the AC closet helps.

You can entice more bees to leave the hive with honey than vinegar