The advance half, and the evening it holds open

The deposit is half the fee, calculated from the figures printed in the profile of the woman you named, written out in the booking thread as soon as the hour is agreed, and settled before she leaves home. It is not a security placed somewhere and returned at the end of the evening. It is the first of two payments that add up to exactly what the profile says.

Which bookings ask for it

Seven descriptions, and a booking needs to answer only one: anything agreed more than twenty-four hours ahead; an eight hour block; a therapist each; three hours or more in one sitting; a room at Schiphol or an airport hotel; a peak date, which includes the large trade weeks; and a couple's first booking with the house. On a working trip the first, third and seventh usually apply at once.

The arithmetic, twice

Two hours with one therapist between the two of you is EUR 720, so EUR 360 goes ahead. Two hours with a therapist each is EUR 1,440, so EUR 720 goes ahead. Halving is the whole of the calculation, and it works on every row of the grid in each profile on the roster.

How it is sent

Card is the usual route, with Revolut, Wise and cryptocurrency available to anyone who prefers them. Bank transfer and PayPal have no part in it. Cash cannot serve, because the advance half is settled before anyone travels and cash only appears in the room. The exact figure and the destination live in the booking thread and nowhere else.

What happens to it if the evening falls through

It is read on a notice scale rather than forfeited flat, and one change of date carries it across intact. The booking terms set out both in full.