<prompt> Human: Hi everyone,I want to open a Roth IRA, but I am having troubles picking an investment firm such as Vanguard or Scotttrade.I have read I should pick one with lower expense ratio, but I was wondering if there were other elements I should consider? Is there one that is better for beginners? Thank you in advance!  <response>: I personally prefer Vanguard. Not only are they low cost, but theyre customer owned and not for profit like a credit union, so theyre not motivated to raise costs like for-profit companies. 