How can I make a claim against a PM for gross billing of unauthorized repairs?

[Christine Kwasny]

I have recently changed PMs after 10 years with the same manager.  First 7+ years were great but then things went down hill.   Since the PM created a in-house repair and maintenance company in early 2024, all repairs have been completed and billed without gaining prior to authorization - as is per the contract - like a blank check on my part.   I am currently auditing the past 15 months of statements, but I suspect this will amount to well over $10,000 across the three properties they previously managed. 

Does anyone have experience making a similar claim against their PM, and is it worth pursuing?