First off, in the strictest sense, Agfa has not been a competitor to anyone for about 3 years or so. So the phrasing is rather moot. They did manufacture sheet films until near the end, when the market dictated that they exit that area. That was a good move by (poor?) management.
As to my being the exception. Well, at 12, I was hardly an exceptional person and if I could do it from scratch then, anyone could. I was totally all thumbs, and broke a hammer, in fact I broke several. I split a screwdriver handle using it as a chisel. I could go on, but the point is that anyone, with a little reading can design a darkroom from scratch.
BTW, I first did processing kneeling on the floor in the kitchen with 3 soup bowls for chemicals and I did the film by the old hand dunking method using clips at each end of a roll.
Back then, they didn't have plastic trays, and SS trays were out of sight for price. I bought aluminum, and the fixer and developer ate through my first set of trays and left a mess on the kitchen floor. This was after I had enough money to buy trays and graduated from soup bowls to 'real' trays. How I lamented the loss of the trays and how I learned not to use aluminum for photography. One of my uncles took pity on me and finally bought me a photo kit.
Oh, I could write a book.
But then I might.
PE