Control the temperature
The cheapest upgrade in brewing, by far.
Sanitation and fermentation temperature. Almost always, in that order.
Wild yeast and bacteria produce flavors no recipe can hide, and they get in through the equipment that touches cooled wort. Thorough sanitation removes most beginner faults in one step.
Fermentation temperature does the rest. Ale yeast fermented warm throws fruity and solvent notes that people mistake for a bad recipe; holding it steady in a tub of water fixes it for about twenty dollars.
Logs make all of this visible. Gravity readings, temperatures and timings turn vague disappointment into a specific cause, which is the entire basis of coaching at a distance.
The cheapest upgrade in brewing, by far.
Numbers explain what memory can't.
No selling without a license, and never distilling.
Twenty minutes, free, on your log and your process.