I opened the door and stepped out into the frigid night, wondering if I'd made the right move. People thought I was crazy. I'd just quit the safest, highest-paying corporate job I'd ever known, and I only had enough money to survive for 30 days. I had one client, a laptop perched on a wobbly folding card table, and a stay-at-home wife and three young boys to feed. I also had a plan — and, over the next 90 days, I ended up generating six figures in revenue without leaving my house. All of it…