So, the question is about
margin requirements for a
Put Spread (Credit).
Let's see what TradeStation says (IMO the best reference for margin & cash requirements in the retail industry):
https://www.tradestation.com/pricing/options-margin-requirements/
Con1991, do you use a
MarginAcct or a
CashAcct in your above demonstrations?
Can you say whether the requirement(s) of TradeStation is the same as TDA or IB? Or is it even different from both?
FYI: with MarginAccts there are 2 requirements to meet:
initial requirement (ie. when opening the position), and the
maintenance requirement thereafter.