It's important to note that you can only get 0% on purchases. I did the same trick as submitter in my self-funding days: all expenses other than rent were defer

It's important to note that you can only get 0% on purchases. I did the same trick as submitter in my self-funding days: all expenses other than rent were deferred for a year. I paid them back once I raised funding (and had the company failed, could have covered it all with a few months salary at a paid job). However, as the submitter mentioned, any cash advance, balance transfer, etc. typically incurs at least 3% interest and/or transfer fees which really hurts potential returns. I'd be amazed if you can find a way to buy any investment vehicle with a credit card, forcing you to use the 3+% cash advance. When you further factor in the time it takes up cards and the low credit limits you'll likely get, this strategy probably won't be worth it.