I answered this for someone earlier today and I hope this helps:
Ehrlich, marquis, and mecke reagents are the most useful reagents IME. Here's the Ehrlich and Marquis on Amazon and I got my Mecke reagent from the Bunk Police. If it's just for LSD, the Ehrlich and Hofmann kits are your best bet. Good luck and I'm glad you want to test what you've got!
Yeah, they're decently priced:
Ehrlich's Reagent https://www.amazon.com/dp/B075G2632T/ref=cm_sw_r_cp_apa_ED-KBbWC11DQR
This one tests for indoles, so it will rule out most RCs. If it turns purple, you either have lsd or 5-MeO-AMT. You can also get this little number:
Marquis Reagent Kit https://www.amazon.com/dp/B075G24TVF/ref=cm_sw_r_cp_apa_IH-KBbXJS4P26
This will narrow the possibilities down even further. If it turns green or black, you most likely have lsd. If it turns gold or brown, you most likely have 5-MeO-AMT.
I really only use the Ehrlich reagent. I cut off a small piece of a tab, put it on a white plate and drop a single drop of reagent on the piece. It can take a few minutes to react but if it turns purple, at least I know it's not some of the bad RCs that are out there