endlessness,
Many of the precursors used (e.g. concentrated H2SO4 & concentrated formaldehyde for Marquis, a 2% Na2CO3 solution for Simon's reagent B, etc.) can be commonly found online and very cheap prices, with the cost of proper protective equipment being cheaper. Many of these chemicals can be easily bought over ebay, Amazon, and
similar such suppliers in gross quantities which can generate enough reagents for thousands of tests for years and years and years (if stored under proper conditions).
Although some of the chemicals exhibit toxicity, it is still possible to make reagents involving safer chemicals which are practically unregulated and can be easily made by anyone with (and sometimes without) a background in chemistry.
I wanted to bring community attention to the ease of creating these reagents (PS: if your fresh batch of reagent seems funky, look up synth in literature, execute it, and let the product do its thing for a few days before testing it against an overpriced 5ml bottle of the same stuff via testing multiple samples of differing substances extensively in order to ensure accuracy).
Lack of education aside, most drug users don't have good finances, and many times I have had to serve as a de facto first responder for people who, right before my eyes, went into grand mal seizures, psychosis, stroked-out, as well as having to initiate CPR on some poor bastard who went into cardiac arrest after he did a line of "H" which was in fact a fentanyl derivative, etc. etc. etc. from drugs which they ingested, thinking that a dealers' word is equivalent to a colorimetric test. I want the public to be aware of how to make these reagents (at least the ones involving safer reagents, such as Marquis, Zwikker, Ferric Chloride dissolved in distilled water, Duquenois-Levine, etc.)
My motivation in posting this is in the hopes impoverished, under-educated and poor drug users, risking their freedom & future in order to get high, may be able to be able to find cheap reagents in order to make massive quantities of these reagents in order to test their chemicals, promoting harm reduction via teaching the poor how to make affordable reagents for testing drugs for the presence of toxins, impurities and similar such pestilences.
I am in touch with a few dozen psychonauts in my community, and I'm almost always the one they turn to after obtaining a novel psychoactive substance in order to determine whether or not its pure, safe to consume, and/or cut with a different poison. Unfortunately, I tend to do around 12-20+ tests per sample, if not more (initially 3 spot tests with 3-8 reagents, followed with TLC if anything looks off (e.g. mixed colors from testing reagent.) I am a big proponent of harm reduction and safety when it comes to recreational drug use, and will do all I can in order to make sure that a sample is as advertised. One reagent test is not enough, which is why I tend to go through multiple reagents at a fast rate.
I am planning on investing in some of the less toxic precursors to create large amounts of these otherwise overpriced reagents in order to share samples of these reagents (after extensive testing in order to ensure that they are on par with commercial standards) freely with everyone who would like to have their unknown drugs tested for free, as an act of charity and service to what is commonly known as The Human Condition.
BTW, do you know of any reliable colorimetric reagent tests for benzodiazepines? I am having trouble finding reagents to test for presence of various benzos, and would appreciate some advice regarding this, as I was gypped out of $20 trying to buy a supposed test kit for RC benzos, and am eager to find/create effective colorimetric reagents for RC (& FDA approved) benzo testing, as problem children such as flubromazolam, clonazolam, phenazepam, the etizolam family, diclazepam, pyrazolam, etc. are causing a great deal of people I know to become benzodiazepine addicts :thumb_dow ....
TL;DR It's important to have at least some chemical laboratory background in order to make some of these reagents, yet you don't need extensive experience. They can be easily prepared en masse for cheap prices per test (e.g. would one rather pay $15 for one vial of marquis reagent 5ml, or would it be easier and more sensible to pay a little extra for the ACS grade reagents to make this reagent, such that a single test would cost a fraction of a penny in lieu of a fraction of a dollar). I'm pissed at how colorimetric reagent producers are ripping off millions and millions and millions of people around the world in the name of "harm reduction," peddling small aliquots of overpriced reagents to to drug abusers across the world, thus making it cost prohibitive and limiting the ability of the proletariat to effectively, completely, test their drugs in order to ensure that it is what they were told it was, and that it isn't contaminated with other drugs and/or misc. toxins. A drug user's budget shouldn't dictate whether they live or die the next time they haphazardly decide to bomb a gram or so of "molly" at their local nightclub.
), and would like to know if you, or other chemists on the forum, may be able to recommend any initial eluent solutions/ratios specified for certain drug classes (as well potential broad spectrum eluent blends for testing extracts from under-researched plants for varying families of molecules of potential interest/value) which would employ affordable ACS-grade reagents which aren't classified as List 1 Chemicals by the DEA. Any/all input from experienced chemists who are well-acquainted with TLC and/or Radial TLC, as well as testing for the presence of varying families of compounds with colorimetric reagents 
