Advice on modelling agency commission - anyone?

[Inadays]

My DSD (17) is about to sign a contract with a reputable London modelling agency. In the contract it states that the agency will take 37.5% commission.

Does anyone have any experience of dealing with modelling agencies, and if so, does this percentage seem about right, or really quite high? Any advice really appreciated. Thanks

Is that on everything she earns? Sometimes it is higher on initial shoot fees then lower later on usage of images.

DD's contract had an awful lot of deductions for expenses.

It's 20% from the model and 20% from the client. Which agency?

Thanks for the replies. I won't name the agency, but it seems that they're going to take 37.5% from her. No idea what they take from the client.
I think we need to ask more questions, as no mention of expenses, or whether the commission is different after a certain length of time. Thanks again.