The smallest orders available online are enough to kill an elephant, and you need a $500+ scale to dose it accurately enough to keep a human from overdosing. And while most human overdoses will be uniquely unpleasant but not lethal, there is definitely the potential for a lethal dose if someone puts a tablespoonful into a drink or something.
Pure caffeine is a uniquely bad thing to have around your living quarters. It's basically a poison (because of the difficulty in measuring dosage and small range between useful and dangerous effect), but people feel very comfortable with it, imagine it's safe to eat, and a big enough chunk of people will act macho towards it.
Honestly, the only reason you should be dealing with powders is if you're making your own 'stack' of nootropics.
Or you can just get a super small 0.25 cent plastic scoop that amounts to normal dose.
No you don't. It's not hard at all using milligram scales < $50. I do it all the time with various substances... including caffeine.
Every gram of secondary solution now has a milligram of caffeine. 2 tablespoons of secondary solution is roughly equivalent to a cola.