Ziv: with any credit spread the margin requirement IS the max loss. That's why the broker requires it to protect himself in case the trade goes the other way. Whether you have 100k or 10k in your account for options you need to know what is your max loss (margin requirement) and gain with every trade and weigh it out carefully before entering a trade. At least that's how I see it.
As to the liquidity issue i donot know what OptionsExpress does but it doesn't seem right that they only bought 4 HTZ contracts while selling 25 contracts for you. The bought (long) side limits your loss while the sold (short) side is your profit. If the open interest on the bought side did not increase by 25 this morning I would be worried bc you dinot have the protection you need for the trade. Maybe that's why you thought the margin req was only 5,500 instead of 9,250. Otherwise HTZ looks like a good trade with a decent gain/loss ratio. My 2 cents.
PS: why is Asher's post deleted? He raised a valid point imo.
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