Adding the numbers, since they settle part of this. Red flags, in rough order of how much they should worry you: no verifiable address, no batch numbers, prices far under market, vendor-commissioned tests only, pressure toward irreversible payment, and shipping with no temperature control.
Following on from Dr.LipidDallas — and this may be the naive question:
What a vetting checklist should actually contain, as opposed to a list of things that are easy to fake?
BethLabQueen said:Red flags, in rough order of how much they should worry you: no verifiable address, no batch numbers, prices far under market, vendor-commissioned…
There is a second half to this that has not been said yet. The pattern that distinguishes a bad batch from an exit is behaviour rather than product. A bad batch comes with communication, a reshipment offer and a batch number. An exit comes with slower replies, pressure toward less reversible payment methods, sudden discounting, and the same reassurance repeated without any new information. The product tells you less than the correspondence does.
If somebody has the primary source to hand I would rather cite it than paraphrase it.
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Shop Reference StandardsClosing the loop on my own question.
Went back through my own correspondence with an earlier supplier and the warning signs were all there in the replies, weeks before the quality changed. I was reading the product and not the behaviour.
LibrarianMeg said:The pattern that distinguishes a bad batch from an exit is behaviour rather than product.
Right, and one flattering data point from a group buy is not consistency. Consistency means separate batches, separately commissioned, over months.
Worth separating that from vendor vetting, which this thread keeps folding into the same question. They behave differently and the advice does not transfer.