I imagine it's legally risky to buy a large quantity, test it, and then resell smaller quantities. That's a shame because the alternative is probably that some folks settle for products of dubious quality and end up getting hurt.
Actually, you just described most of the tele-health and compounding pharmacies that carry GLP1s!
Where do you think Hims, Ro, Brello, or the rest get the APIs they sell to their customers? They get them from grey market suppliers in China. They don't go to Ely Lilly or NovoNordisk and say, "politely sir, may I skirt around your IP and sell your drugs for 10x what they cost instead of 10,000x what they cost?" Hopefully, they test them and filter them and use sterile/pharma processes for what they sell to their customers. Well, except for the Medspas, those are just wild west snake oil farms.
It probably is, but that does not stop people from effectively doing it. There are a number of groups that specialize in conducting group buys, doing a bunch of testing on randomized samples, and then shipping out the product to individuals.
Also, if you plan to be on it a good long time, you can buy a bunch of kits yourself (a kit is 10 vials), run a bunch of tests, and then just have a nice stockpile that will last you years. The testing will likely cost as much or more than the product itself, but given how inexpensive the product is, you still come out way ahead financially.
>I imagine it's legally risky to buy a large quantity, test it, and then resell smaller quantities
It is illegal, but it doesn't stop people from doing it. In fact, if you don't have any sort of test results for your peptides people will absolutely avoid buying your wares until you have them. Purity and mg/ml are the 2 basic test results that any shop worth their stuff will have.
Yes, I believe most people buy directly from somewhat shady Chinese factories. I tried contacting a few and they all refuse to meet or send samples from within China, so I assume what they're doing is illegal in China. In the US, it's legal to sell them as a "research chemical" but the FDA is cracking down on companies that are clearly engaging in b2c.
There's this company that offers free testing: https://finnrick.com/
Another popular testing company is https://janoshik.com
Some other useful resources: https://graymarket.substack.com/ and https://glp1forum.com/
There are a few subreddits as well.
FWIW, I never ended up buying any myself.