业主群 for your particular compound may be found on WeChat social circles.
You would have more chances of finding owners association on WeChat if residential communities are larger and newer. Recent buyers have more to gripe about en masse after rushed deliveries by developers (to avoid accruing penalties from breach of contract).
Such relatively younger owners are keen to search each other out for strength in numbers.
One caveat is the most vocal "leaders" of the pack, or those with legal background, would be sought out by the opposition for pacification in private.
The grim reality of these owner associations is that personal benefits would be sought by the few over the good of the collective when given the opportunity to choose. It's not always a zero sum game in the Mainland when bilateral negotiations are concerned for multiple parties.
Start a virtual owners association on WeChat as 群主 if you can't find an existing one. Participants gradually increase in numbers as online group discussions of how your developer or property management suck. Eventually the WeChat community of 12 angry owners may morph into actual physical encounters. Nothing like sharing common goals and a common enemy to unite total strangers.
For older residential compounds, regulars who are often seen exercising in the public spaces may have formed clusters of their own cliques to address matters with the property management pertaining to resolving their specific needs. Accost them at your own discretion.
Property management fees may include 维修金 (renovation fund) which property management allegedly uses to fix things like elevators, or repair the cosmetics of common areas. If their books aren't transparent, 物业 may skimp regular servicing to pocket more profit.
That's when you and your fellow compatriots threaten them with #12345 national hotline complaints, or with the local 经开区, if initial protests failed to reap results. The developer of your community may still operate your property management in-house, or under a separate business entity if not outsourced/contract out. Know thy enemy.
Owners association are feared by property management, so naturally they won't navigate you to a congregation of owners to protest against them.