Hi all, i'm new to trading and i made my first wallet of bitcoin in CoinBase...now i would like to buy some altcoin but if i would like to transfer bitcoin to exchange like bittrex or other they ask me an high fee for tranfer like 12$ for transfer 100$ of BTC....is it possible? How can you  make good trading if everytime you have to transfer money from wallet you have to pay so high fee?  I did mistake something? thanks