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I am sorry you are dealing with this situation. While this is an appropriate case to be heard in small claims. Typically small judges will not order injunctive relief, that is order a defendant to due a certain act (i.e. put fence back as it was). However, small claim routinely awards money damages for the amount you would have to pay a person to repair the fence in the condition that it was prior to the neighbor failing to perform the work as agreed to. It would be beneficial if you have to go to court to have bids to repair the fence include the amount as part of your request for damages.
An alternative to small claims would be to attend community mediation. However, given the unreasonable nature that the neighbors exhibit this may not be a viable option as it requires their cooperation in attending the mediation.
Here is a link to California small claims information and forms: http://www.courts.ca.gov/partners/documents/smallclaimschecklist-en.pdf
All my best & encouragement.
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