In order to obtain this achievement you need to go to the black market and when entering a guard will ask you to tell him the password which is Win-win and ready you have the achievement and the black market for be able to trade with sellers.
English

Para poder obtener este logro necesitas ir a mercado negro y al entrar un guardia te solicitara que le digas la contraseña la cual es Win-win y listo ya tienes el logro y el mercado negro para poder comercia con los vendedores.
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