The balance on arrival is what remains of the ladder price, settled privately with the therapist in the room at the outset, by cash, card or crypto.
A hotel settles its account at the end of a stay, downstairs, on a folio that itemises every charge. The house reverses both habits. What remains of the fee is settled upstairs, privately, in the first minutes after she has come in, and nothing about it appears on any hotel bill.
For nearly every reservation the balance is exactly half, because the other half was sent as the deposit when the office accepted. For the single exception, an hour or two requested for today by a guest the office already knows, it is the entire fee. Three cases show the range:
Banknotes may be euros, dollars, pounds, francs or another major currency, converted at the day's rate, which spares a guest just in from New York or Zurich a search for an exchange office after dark. Card is accepted, and so is cryptocurrency. A word in the thread about which the guest intends to use keeps the moment short.
Cash has a fixed place in this arrangement: it belongs to the balance and to nothing else. Confirmation happens while she is still elsewhere in the city, and notes cannot travel ahead of her, so cash is never the means by which a reservation is confirmed.
Settling at the outset is a courtesy to both sides, since the subject is closed before the evening begins and does not return. Questions of gratuity are addressed in tipping and settling up, the first half is explained under deposit, and the figures themselves live on the price page.