Normally would never both with odd/mixed lots but started something with small initial account size and would like to position size according to equity percentage-which basically means I would like to trade odd-lot share sizes. I've searched and googled but still have some questions: 1) ARCA charges .03 PER SHARE for odd-lots. If it is a mixed lot, am I only charged for the odd-lot size? For example, 560 shares, 5 round lots, and 60*.03 for the 60 remaining shares or is the whole ticket (560) charged? 2) BATS/EDGX/ISLAND may charge less for odd-lots but not the highway robbery of ARCA. BUT what if someone who routed through ARCA, either market order or limit, takes my order on another ECN, am I charged .03 by ARCA? For example, I post 20.02 on EDGX and someone crosses with me but routed through ARCA? 3) If i place a limit order to buy at the ask or sell on the bid (effectively a market order) and the NBBO is ARCA-will i be charged .03? [For clarification] My goal is to find the cheapest ECN/Routing for odd/mixed lots without getting raped on fees and executing quickly. EDGX does well enough on liquid stocks but not so good on a few others I trade often. In addition even if I place a limit at the bid/offer to get executed, execution is iffy and i've missed prices. I've heard/read conflicting things so any experts or gurus help would be very appreciated!