1 BTC is plenty to start. Knowledge about the protocol, systems administration, good business acumen, and creative financial engineering are what separates the pro from the hobbyist.

Your "edge" as a node is your ability to select, size, and sustain high-demand channel liquidity at competitive prices. Your revenue can disappear if some other node decides to compete with you. It's a race to the bottom to find out who can price the liquidity most effectively.

It's not exactly the kind of business you want to depend on to fund your lifestyle, unless you're confident in your edge and competitiveness. With automation, a node could become a 0.1-person operation (mostly passive).