A bit about how service has changed in few last years. Now all Top London escort agencies ask models to provide selfies and add them to public profiles same as some short videos where London escort models introduce themselves (some saying short "hello introduction, some just turning around to show client figure or face). It's all public on each London escort model's portfolio and for clients means more than professional photos. In this case potential client can have a realistic view of the model even before he makes a booking and pay money.
Some time ago Escort models didn't want to put their selfies on the website, not even send to clients via WhatsApp. All that the client could see were professional photos. Obviously, they are high quality and with Photoshop. So there were sometimes complaints from clients that the model he booked didn't look life same as in photos. Some Models looked older, not so slim, or the bust size was smaller than it looked in photos. In this case, when a client in life don't like what he sees, he cancels the booking and nobody gets their money. It's bad for girls who spend time and go for booking and bad for the Escort agency as they lose clients. So few years ago almost all London escort agencies started to provide for clients models selfies.
Before that, some "TOP class" clients (celebrities, movie stars, and millionaires) to avoid this possible misunderstanding with "NOT good models" did castings for escort. What those it mean? Their Managers called a few different London Escort Agencies and booked from each agency a few different models. They all come to some fancy hotel, get paid for 1 or 2 hours, drink champagne, dance, and chat, and at the same time, this Manager is checking all models (without any service) and choosing the best looking. Rest sending home and booking the next few models. All chosen models get paid for each hour until the Manager has selected the needed amount models and then all go to some party place where there already is this "TOP class" client. For models, this was a better way to earn more money but for clients now is much better with selfies on their portfolio. These top-class booking is not happening every day, but if you are lucky enough and look good, at least once or twice a year you can get to a party like that. Especially on New Year's big party.