if trading ~1k RT per month, you can get ~$3.78 per RT. then you can apply membership to cut down your fees ~$1.40 per RT by paying $700/month for leasing a seat.
$3.78 - $1.40 = $2.38 + ($700/1k) = $3.08 per RT, thats about $3080 per month / ES ~250 ticks