I completely disagree about "Nothing focuses the mind on finding revenues like being broke and needing to make the rent." I know that a lot of people out there believe in this "desperation leads to solution" mantra. But I don't. I work much better and I am much more focused when I don't have to worry about bills.
I started to sell my product from month 1, but wasn't able to generate revenue from month 1. I have a SaaS for restaurants, the sales cycle is longer than a month, no restaurant (around here) close deals at the end of the year - this I learned from experience, but also from successfull and experienced entrepreneurs from the same market; also advised by these successful founders I am offering a 3-month free trial for the first clients. The advice actually was "you will only charge after the 10th client, you need social proof first of all, so give your product for free and then charge after the 10th early-adopter."
So, there is no way I can be profitable before March or April. Ok, maybe I am no sales wizard, maybe I am not good enough on this founder thing. But the point for me is, I am broke, and I already started my company, and I can't make it profitable. As I can't choose option 3 "go back in time and found another business" and I am not ready to quit this business, I will take funding.