P2P exchange of fiat currencies


I’d like to know where I can find (if exist) a P2P exchange of fiat currencies, like this:

In my country, this institution is called “house of change”, I guess that in english is called “bureau of change”, but, in this institution, it’s who determines the price of sell and buy.

In an P2P exchange (like the Poloniex), it’s the user who determine your price.

I have an amout of BRL and I want buy USD by BID price. This is impossible in my country! Here, the “spread” of the institutions is 1000 or 2000 pips! This country is insane!