If I am to buy out all the under price option, what guarantee do I have they have enough btc on your exchange to settle trade (in the unlikely event that bitcoin go up to 600 over night)?
These are cash or nothing binary options. The sellers need have enough margin to cover the maximum possible loss (i.e. 0.01 BTC for each option). So nobody can default.
I see.
Payout is 0.01 btc regardless of price once reach on settlement date only. Then being a seller is better once the price of the option reach 0.07 or higher as the loss is only 0.03 at most.
What is the fee the exchange charge?
I just added the option price calculator to the trading interface. So now you don't need to write your own program or build a spreadsheet to price the options. I hope this can help you hunt mispriced options more easily. You can check here for the update https://bitcointalksearch.org/topic/ann-coinutcom-the-only-bitcoin-options-exchange-beta-821889