So, as a bit of follow-up, all last year he did a monthly income and expense report about his business, often detailing what worked and what didn’t, what his predictions were, and what the basis of those predictions was. It was wonderfully detailed stuff: data you almost never get to analyze unless you’re doing it yourself.
So on January 1st, he did an income report not just for December, but for all of 2019. It’s remarkably open and informative.
Oh, and because I’m sure he wouldn’t mind, if you think you’d dig the stuff he writes, he has a Kickstarter for his “Godsverse” novels running for the next six days.