so of course you fix your neighbors roof, otherwise they will not help you in the future.
You know what they say about common sense.
Back to my condo story. A few years into my fight with them over the leaky roof, a radiology office opened up on the 1st floor’s commercial space. Very quickly the 2nd floor residents came to find out how loud those MRI machines get, and wanted everyone to chip in for installing soundproofing. At that point 3 other units on my floor also began experiencing leaks on their ceilings because turns out water doesn’t stop at apartment boundaries. The people who were voting down fixing the leak were very angry at us for voting down installing soundproofing. They just couldn’t wrap their brains around the idea of shared benefit until it hit them in the face.