I wholeheartedly agree about the first people, and I wasn't referring to them when talking about exporting software to Earth. It sounds like Elon plans on having an elite team start out the colony, building the domes, etc, and then selling living places to "regular" people who have a lot of money. Those people will certainly not have to spend every waking second of their day working to survive; getting that in place was the goal of sending the first people initially.
well, if that's the case where the $500,000 comes in much later, and there's ways to make a decent living on Mars, then it's certainly possible. But again, I still think people need loans, they don't have $500k sitting around. And lenders will only give out loans if there is a good chance of paying it back. If someone takes out a loan, goes to Mars, and refuses to pay, what is the lender gonna do? It costs $500k just to go to mars, it's not like they're gonna send a bill collector after them.
Just make all banking on Mars electronic. If you don't pay your bills, you flat-out don't have money. This even works in a Free market version, as banks will probably cooperate on debtors even while they're competing everywhere else.