I didn’t remember some details, like whether he started before or after you met.
He’s not going to find a job that pays him residual income. No company wants to do that, since it’s income they don’t keep. I’m sure there are some jobs out there that pay residuals, but the best way I can think of to create residual income is to either write a book or make a movie that keeps paying some kind of royalties or to create your own business that sets up a system where people pay by subscription.
I’ve heard of situations where a sales person continues to make an income on sales of things like subscriptions (the salesperson makes some each time it’s renewed), but anything like this will eventually slack off or peter out, since over time fewer people will keep renewing.
Here’s a big point for him to consider: Computer and data work has a much better potential to provide residual income than many other fields. Once you write a program, the effort is done and you can resell it many times over at a fraction of a cost (to you) of the original. Just print a new manual and burn new disks and you’ve got another copy at a cost of $10 to $20.
Is it possible he could work out a deal to sell the software he’s written for his work to his own company? That might help move him over to a computer job, if he wants, since they’d want new versions with improvements and bug fixes.
He might also be able to use some type of auto-updating feature and, instead of selling the program once for each company or set of licenses, could sell it as a subscription program. Then a company would pay him a set amount per month for a certain number of licenses and that would include updates and bug fixes. One advantage is that once he fixes a bug for one company, he can push it to other companies as an update as well.
That’s a few ideas you might want to forward to him. For what it’s worth, my business is based on a model like this. I sell subscriptions to a data service. My clients pay me monthly. I have a simple program that runs on their computers and the program that runs on my computer does all the hard work (that includes the processes I don’t want others to be able to copy). As of now it’s automated so the data is delivered to them regularly, but I’m still working on the control programs. When those are done, the data processing is automated and managing the business will take very little time. He might be able to set up something similar with the program he uses for his job.