lisa_labSD said:

Prices dramatically below market are the strongest single signal, and the reason is arithmetic rather than suspicion.

Genuinely useful, thank you. I had the facts and not the framework. Printing the relevant bit and taking it with me.

Clinical perspective, offered as context rather than as advice. If two explanations both fit, the useful question is which one predicts something the other does not. That is answerable; arguing about which sounds more plausible is not.

sean_dublin said:

Shipping damage protocol for vendor vetting orders: if your package arrives with visible damage, temperature excursion, or broken vials: Photograph…

Filing a mild objection. Mild because I might be wrong; an objection because nobody has addressed the case that does not fit. Not convinced. The evidence being cited is consistent with the conclusion and also consistent with two other conclusions nobody has ruled out.

Adding the numbers, since they settle part of this. Practical: whatever you change, write down the date and the reason. In three months the reason is what you will have forgotten, and the reason is what makes the record worth having.

That is the short version; the long version is somebody else's post.

Moderator note: the sourcing question belongs in the vendor section and has been split out. Carry on.