Quote from marameo:
Does it have to be an iron fly? How about put-only-fly or call-only-fly?
I assume bid/ask spread plays a major role when it comes to open/close the trade. Also, commission will affect any profit/loss; say I want to trade 250 of those flies, that's $1k fees just to open the position (I assumed $1 per option).
According to the guy who taught me, iron is the key due to different behavior of OTM calls and puts. Plus liquidity is better (.03-.04 spreads are common). Commissions are a big factor, of course. He uses OptionHouse where 250 IBs would cost $162.5. (15c/contract + $12.5). That means a break-even point is less than 2c away from an entry price.
I tried this trade with TradeMONSTER (50c/contract).