Balance on arrival names the share of the fee handed to the therapist at the door of your room, as banknotes in any major currency, a card payment or crypto.
Someone who has just cleared passport control often carries three currencies and no euros. The balance is designed with that traveller in mind. It is whatever remains of the ladder price after any deposit, and it is settled in person in the first minutes after the therapist steps into the room.
Notes in euros are fine, and so are notes in any major currency, taken at the rate on the day, so dollars left over from a transatlantic inbound or pounds from a morning flight out of London need no exchange counter first. A card is accepted. Cryptocurrency is accepted. Say in the thread which you intend to use and the handover takes seconds.
Cash has one job in this arrangement and only one: it settles the balance. It cannot serve as a deposit, since a deposit has to reach the office before she leaves, and banknotes only reach her when she arrives.
For almost every booking near the airport the balance is half. Any room at Schiphol or an airport hotel carries a deposit, so the arithmetic is short: a first hour at EUR 180 leaves EUR 90 for the door; a pair of therapists booked for three hours, EUR 1,080, leave EUR 540; an overnight at EUR 1,250 leaves EUR 625.
The balance is the whole fee in a single case: an hour or two of massage, asked for that same day, by someone the house has already welcomed as a client. Because airport addresses always carry a deposit, a traveller meets that case only in a room in the city, say a regular flyer spending the evening near Centraal before an early train out to the terminal. It is the exception, and it stays narrow.
Settling at the start means money is not a subject for the rest of the visit, which helps when the visit ends with a taxi or an alarm. Figures are on the price page, the advance half has its own entry under deposit, and gratuities are taken up in tipping after a Schiphol hotel massage.
One hour EUR 180 through to eight hours at EUR 1,250. Forty to sixty minutes anywhere in the centre; the Schiphol airport hotels by arrangement.