Well each agency has his own percentage. 25-50 or even 70... i really don't know.
Here agencies only answer girls phones, they don't bring customers, the customers are from the ONLY escort site (is not the only one but is the most popular) so the agencies are promoting on the same web site like the independent escorts, while in the UK or NL they have their own websites.
Regarding photos, i just changed my hair color, and couldn't use my professional photos, where i was blond. I am having tomorrow a photo session which i am going to pay, as i am independent.
And i will update my add with the new professional photos, and as i said before, and it is written even on my add ... temporary a going to use those ones, which btw i like a lot ... (monique is a great photographer)
I hope i answered all your questions