Fidelity used to be good about that, only one commission on gtc orders. Now they are as you say, commission every day of partial fills. I don't use aon orders because for whatever reason I don't get my shares. I just try to put in large orders and assume that I will pay several commissions. Sometimes I am pleasantly surprised.
Think you should check and verify that with them. Brokers charge a commision for making a trade for you but if your order is not completely filled you have not completed your trade.
I am 90% sure you will find that you are able to make your trade without multipul commisions. I am only not sure because i have not used schwab.
I use etrade and do not have a day trade account. I get charged when my order is filled or if it is a partial and i cancle or change the pps.
One thing for sure. If you are sitting below the ask with an aon order you will not get filled till the trend turns down.
Once selling starts and the mm sees many selling orders on level 3 you will get filled with short shares and the mm will cover them a couple hours after you have your shares. In the end you will be saying when you buy the pps always drops.
Try it with your next trade. Worst thing that can happen is you are out 8 bucks. But if i am right you will make that money back when it ticks up after yor buy instead of always making you regret your buy
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