Of course, when I first started growing, some 40+ years ago, there was no "internet", as such, with which research of this kind could readily be done. So, lacking friends who grew, and who could modify my beliefs, I just kept making the same mistakes. I already have cut a hole for a 20" box fan, until I can examine my growing area for more needed modifications. That area, which I use for sprouting, cuttings, and vegitative growth, is in the attic, and it does get warm up there...the fan seems to have already dropped the temp by 10 - 15 degrees fahrenheit, to the point where it feels comfortable, not overly warm.
Next comes a hydroponics system, to replace the dirt growth I've always used. Many, many thanks, and more to come I'm sure, for setting me straight on issues that I've overlooked or misunderstood!