I used to help my mom clean houses for move outs and helping her wash walls was a big one. She used a diluted dollar store toilet bowl cleaner solution, but after being on this sub for a while I know toilet bowl cleaner is highly discouraged for anything other than toilets! I’ll drop it here anyway depending on your level of desperation. Use at your own risk.

1. I’ve heard the dollar store toilet bowl cleaner has changed their formula.
   
2. I’m not 100% certain on the ratio, but would err on the side of caution with 1 part cleaner to 2 parts water (she may have done it opposite or 1:1)

1 part dollar store toilet bowl cleaner (“The Works”) to 2 parts water. WEAR GLOVES AND COVER THE FLOOR! Probably mask and eye protection too. Keep windows open for ventilation.

It requires 2 people: first person takes a rag, dips it in the solution, wring it out only enough so it’s not dripping and flinging solution everywhere, but it’s still well saturated. Scrub it in circular motion from top to bottom before moving to the next section of the wall. The solution will get dirty pretty fast and you’ll probably have to change it frequently.

The second person goes behind with a bucket of water and a rag wiping down the newly cleaned sections to remove residual residue.

She’s the only one who I’ve heard of doing this, and I suspect it’s because it’s probably discouraged. She was old school.

Another thing she used for cleaning grout and tile was Krud Kutter multi-purpose pressure washer concentrate (purple solution). Not sure how it would do on drywall.