The tek you link starts from grain spawn. You don't need sterile conditions at all to propagate loads of mushroom species if you're already starting with a robust dikaryotic culture, especially those of wood-decay (lignicolous) species. That's one principle of "spawn". And there are some dirtier methods that can work, e.g. just dumping spore water onto suitable unsterilized outdoor mass substrates.
But I've seen home cultivators who manage to do things like culture single spore isolates, breed and select dikaryons, clone wild specimens, and fruit very fussy species, all indoors with basic and improvised equipment. That deserves respect.
Yeah I've seen the instructions online for building your own flow hood, that whole subculture is pretty nuts. If you haven't read Hamilton Morris's story about the guy who created the Penis Envy psilocybe strain, it's pretty interesting both because of the content but also because it involves a lot of folks you probably know or at least know of if you're into the amateur mycology thing.
That is a wonderfully written article.
I got a pre-packaged kit for oyster mushrooms (1). I followed the instructions carefully, but it's been two weeks and I'm starting to think this project is a failure.
(1): http://www.amazon.com/Back-Roots-Organic-Mushroom-Mini/dp/B0...
How much could I expect to harvest using this method. Does this translate to a signification reduction in cost?
You might see a cost reduction if you learn to grow some of the more expensive varieties. The yield is tricky because there are other variables that factor in like ambient temperature/moisture and the prescribed ranges are rather large. I'm working on my first grow kit, and so far the yield is zero :(
https://courses.biology.washington.edu/biol440-spr16/folders...
Also the mycelium has a pleasant almond smell, so that's a nice whenever you go downstairs to check on them. The hardest part is figuring out what to tell the Petco employees when they ask what kind of cat you have.