How does sharebuilder charge $4 per investment?

They say $4 per investment then $15.99 per trade. Does that mean they charge $4 per Stock or $4 every time I buy more shares regardless how much I pay?
for example,
a) if I buy 10 stocks I pay $40 one time or
b) If I buy those same 10 stocks I pay $40 but if I want to buy more shares of the same stocks I have to dish out another $4 even if I only want to buy as little as $5 worth?
and if I want to sell my stock I have to pay $15.99 everytime I sell or trade shares? or stocks?
If they charge per buying and selling of shares then it wouldn't be worth it unless you invest at least $200 per stock each time ($4/$100 x2 = 8%commission. The less you invest the higher the percent commission on each purchase) if you want to diversify and have automatic investing then that is super expensive. $200 x 10 stockes = $2000 per month to invest.

so, please answer if you know. Is it a) or b) and explain.

The $4 fee is only for the automatic investment plan. It applies each time you make a buy. Basically it is $4 per stock, per buy transcation. The dollar amount of your trade doesn't matter. So if you buy a stock it costs $4, regardless of the amount of shares, up to 1000. If you buy more than 1000 shares, there is a surcharge. The next time you buy that stock, it costs another $4.

You are correct about the commission percent decreasing as the amount invested goes up. But your math is off. A $200 investment at $4 commission = 2%. (4/200=.02, *100=2%) Rather than investing $200 per stock into 10 stocks, invest $500 per stock into 4 stocks. That reduces your commission to 0.8%. (My personal preference is to never pay over 1%. I try to stay below 0.5%) You can change the stocks you buy each month, so you are still investing in 10 total.

Also, as you noted, the $15.99 fee to sell is high. So unless you intend to buy and accumulate, you would be better off with a different broker.

A. They have different programs to choose from. The program your looking at works like a drip. The money is taken out on Monday and on Tuesday you will get market price for the stock your purchasing. If you plan to do this 10 times a month, dollar wise you may want to look at the $20 plan a month that would allow for you to do this 25 times, You will save yourself $20 bucks. All these are dollars amounts on Mondays, so if you want to buy lets say 100 shares of a stock you can place buy and sell orders anytime the maket is open.

Hi,

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