My Property Management Company Is Not Disclosing Fees

Location: California

Sorry I don't know exactly what area of the law this would fall under so I haven't added a flair.

Okay, so here's the situation. I own a property that I recently started using as a short term rental because I moved elsewhere and wasn't using that property much. Since I am not living close by, I hired a vacation rental management company to manage it for me.

I am listed on Airbnb as well as a couple other sites.

As per the contract with the company, I pay them 20% of the nightly rate of all bookings. There are no additional fees outlined in the contract.

Here's my problem: When I got my first invoice from the company, it included their 20% fee, cleaning fees, and some minor purchases which was all normal and authorized. However, there was an additional insurance fee for $75 added to each booking. This additional fee is not mentioned in our contract. When I contacted them and asked them what this fee was, they said it was a policy they purchased for each booking and they add it onto what the guest is charged per booking. Therefore they invoice it back to me for reimbursement, because everything paid by the guest is paid directly to me. They told me it was a "pass-through" cost and implied that the entire amount was paid to the insurance provider. They also told me this cost was non-optional.

The fee felt really high, so I also asked them to provide some documentation that shows exactly what is covered and what the cost is. They simply provided me a short write up explaining the cost and what is covered, but they did not provide any actual documentation from the company.

I did my own research and found that the actual fee for the insurance tier they claim to provide is actually less then half of the $75 fee.

I came to them with this information and asked them why I was being charged so much, and they basically told me this is our structure and we don't need to explain anything to you. They flat out refused to answer some of my questions, basically saying this is our company policy and if you don't like it you can leave. They also told me that their charge 'might be' higher than the insurance charge to cover admin costs.

This feels very deceptive , because not only did they fail to disclose what this fee was actually for, they actively misrepresented what it was for, and they are still not willing to tell me exactly where this amount is going. Additionally, I had never agreed to pay this extra admin fee - because it was never disclosed to me.

Do I have any legal ground to stand on? Is there any way to get the extra money I have paid returned to me?

I'm happy to provide more information if necessary.

Thanks to whoever takes the time to answer.