Hi,

A little hard to answer the first part of this question: stocks or futures? :-)

To the second part, brokers charge for buying and selling - in futures called a 'full turn' or 'round turn' (buy=half turn, sell=half turn). The full turn usually just includes the broker's commission (variable depending on brokerage) - so it's important to add exchange fees to the figure to get a final amount.

the seeker