deiye, when you clean walls for pesach with a wet shmata and soft scrub, you don’t need to paint anymore. soft scrub (done right) does a wonderful job. it gives it a fresh look.
As long as you dont try that on ceilings. I did that one year and what a streaky mess it left, it was worse than in the beginning. Painted ceilings arent easily cleaned. I learned my lesson good.