I don't sell Calls against Puts. I sell Puts against Puts and I sell Calls against Calls. If you want to sell a call or a Put, know that #1 you have to have a margin account, #2 you will be naked & #3 you will have to have enough money in your account to cover the potential losses. There are people out there that do sell naked options to collect premium but it can be very dangerous.
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