Knock Neighbor Once Before Building Management

Knock Neighbor Once Before Building Management sounds like a micro-optimization until you are on Line 1 when the carriage smells faintly of hotpot from someone's lunch box.

Someone in our WeChat building group once paid ¥8 for a watermelon chunk that tasted like refrigerator regret. The fix took less time than telling the story.

Try this once: write the rule on your phone lock screen for three days. If it survives, it is yours.

Not gospel.