E*trade charges one commission per day, not per trade or per order. So if you get 6 trades today for 40% of your order, you pay a one time commission.

If tomorrow you have one trade for same order for 10% of order, you pay another commission.

If the third day you complete the order on 9 trades, you pay only one more commission.

Total 3 trades @ 4.95 or whatever your personal trade cost is from them.