What about industrial projects?

Hello

I am not interested in games, I dont want to be in the marketplace, my work is on industrial projects that I sold 1 product for 1 client, and the content in most of cases is secret. I want to simulate professional enviroments for training and marketing.
How much and how I pay for this kind of works? 19$ dolars per month + 5% of the cost of the project??

Thank you very much in advance.

That sounds like a work-for-hire arrangement, in which case there are no royalties on your revenue. If you end up making a product that is sold to consumers (rather than a custom built solution for one client), then royalties would apply.

Thank you.