Sorry if I hastily misjudged you but here are the FACTS. 1. You're not allowed to make a cap contribution and scam by trading off someone else's membership. Even a prop firms. For all I know misrepresentation could be a felony. (defrauding a publicly traded corporation etc.) 2. You could probably lay down 200k on an IMM and get a loan on the balance. Consider this possibility: The cost of trading rights privileges (seats) may implode any day. CME stock is getting HAMMERED.
TCA are still offering something along those lines for futures, they say they will allow other instruments in certain circumstances. Maybe the London office could advise you better. My understanding was that this deal is not that great if you have a proven track record and do high volume.