我就是给你个链接，具体如何操作，自己去看吧。实在不行找个律师聊一聊。你这个问题，幸亏法律在你这一边，但是人家不理你，你不下本钱是讨不来钱的。
https://schorr-law.com/property-line-fence-rules-california/
- Shared Responsibility: Under the Good Neighbor Fence Law California, adjoining property owners are presumed to equally share the cost of constructing and maintaining a boundary fence.
- Written Notice Requirement: The California Good Neighbor Fence Law requires a 30-day written notice before building or repairing a good neighbor fence, outlining project details and expenses.
- Disputes Over Costs: If a neighbor can prove the fence does not benefit their property, they may contest their share under California fence law provisions.
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