一般的online broker好像都不要手续费，取出来的时候才要

取出来要交%的手续费呢?是根据earning的百分比来交的吗?

some account closure fee usually, <$100, not %

才100元吗?那是不是还有别的费用啊?难道N年后,银行就赚100块?

You can find such information in the broker's webpage. For example, if you want to open a ROTH IRA account in vanguard, you can find information at

https://flagship2.vanguard.com/VGApp/hnw/content/AccountServ/Retirement/ATSRothIRAOverviewContent.jsp

Account fees and minimums »

• For most Vanguard funds, a minimum initial investment of $3,000 per fund to open a Roth IRA.
  
• No enrollment, transfer, or advisor fees.
  
• Low expense ratios that vary by fund.
  
• $10 annual custodial fee on each fund in your Roth IRA with a balance of less than $5,000.

If you know the symbol if the fund you want to invest, you can also check in morningstar.com. It covers many brokers.

the answer above on 6th floor is more complete. here i make some additions to my previous post

1. open account - usually free (this is what i meant earlier)

2. trading fund / stock - depends on the broker commission schedule

3. yearly maintainance fee - depends on the broker service charge schedule

4. account closure fee - usually some charge, check the brokder service charge schedule