What a marvelous thing you did!!! It is always a terrific high to do something so challenging and have it turn out well.
As far as building systems for a living, I did that for three years and made no money at it. I made my money repairing systems. Building new systems and making money at it is difficult due to the competition of big companies buying parts in bulk. They buy the best parts at reduced prices in bulk and then mass assemble them. You as an individual can't beat their prices.
But don't give up that knowledge. I would love to be a bench technician again. That's my fave. I love making broken things work again.
Great going, Mary!!!!