What is the highest leverage that can be used in money won in any contest
If your account is in Dukascopy Europe you could use 1:300. https://www.dukascopy.com/europe/english/forex/forex_trading_accounts/margin/
Transactions conducted in the SWFX marketplace may be done on a margin trading basis, enabling a client to execute trades larger than the deposit, amplifing price movement effect. The multi-currency exposure of the account is limited by the total trading line which is calculated by multiplying the Equity of the account by the leverage agreed with Dukascopy Europe. By default the initial leverage for regular trading hours is set to 1:100, which allows to increase exposure up to a 100 times the amount of the equity, but can be set up to 1:300 by request (restrictions may apply).
El apalancamiento inicial durante horas regulares de negociación se pone a 1: 100, lo que permite incrementar la exposición hasta un 100 veces la cantidad de la equidad, pero se puede ajustar hasta 1: 300 a pedido del cliente (pueden existir restricciones).
Open trading account